Re: [Help-glpk] the theoretic formula about the integrality gap for MILP and 0-1 knapsack integer programing model

[xypron . glpk]

Hello David,

see
https://en.wikibooks.org/wiki/GLPK/Known_issues#MIP_gap_reporting

Best regards

Heinrich Schuchardt

-Ursprüngliche Nachricht-
Gesendet: Donnerstag, 03 Dezember 2015 um 06:10:20 Uhr
Von: "usa usa" 
An: help-glpk@gnu.org
Betreff: [Help-glpk] the theoretic formula about the integrality gap for MILP 
and 0-1 knapsack integer programing model
Hi,

I would like to find the theoretic formula about the integrality gap for

1. Mixed integer linear programing model  and its linear programming
relaxation
2.  0-1 knapsack integer  programing model and its linear programming
relaxation

Sometimes the gao may be called relative error or approximation ratio.

I would like to see the formula that express the gap mathematically.

Any help would be appreciated.

Best Regards,

David
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Re: [Help-glpk] Help-glpk Digest, Vol 128, Issue 12

[xypron . glpk]

Hello Faiza

install.packages("Rglpk")
should be what you are looking for.

Best regards

Heinrich Schuchardt

http://www.xypron.de

Am 27.07.13 um 12:59 schrieb Faiza Hamdi

> bonjour
> j'ai installée la dernière version de R et qui est "R version 3.0.1 
> (2013-05-16)"
> et quand je voudrais télécharger une fonction j'utilise 
>  > install.packages("ici j’écris le nom de la fonction")
> il y a certaines  fonctions ça marche et il n y'a pas des problèmes, alors 
> que lorsque je mis:
> 
> install.packages("Rglpk_solve_LP")
> il m'a dit
> 
> Warning message:
> package ‘Rglpk_solve_LP’ is not available (for R version 3.0.1) 
> je sais  pas quel est le problème 
> je suis coincée a ce niveau là, prière de me guider.
> merci pour votre
> Cordialement
>  
>  
> 
> 
> 
>  De : Heinrich Schuchardt 
> À : Faiza Hamdi  
> Cc : Help Glpk  
> Envoyé le : Lundi 22 juillet 2013 18h59
> Objet : Re: [Help-glpk] Help-glpk Digest, Vol 128, Issue 12
>  
> 
> Bonjour Faiza,
> 
> le projet R se trouve sur
> http://www.r-project.org/
> 
> La version actuelle est R3.0.1.
> 
> Tu y trouve les liens pur le télécharegement comme
> http://cran.univ-lyon1.fr/
> 
> Si tu as des problèmes avec l'Anglais veuilles essayer
> 
> http://www.google.com/translate?hl=en&sl=en&tl=fr&u=http%3A%2F%2Fwww.r-project.org%2F
> 
> http://www.google.com/translate?hl=en&ie=UTF8&sl=en&tl=fr&u=http%3A%2F%2Fcran.univ-lyon1.fr%2F
> 
> Cordialement
> 
> Heinrich Schuchardt
> 
> 
> On 22.07.2013 14:12, Faiza Hamdi wrote:
> > Merci pour votre réponse
> > est ce que vous pouvez me donner un lien qui me permet de télécharger
> >   une version de R la plus récente sachant que j'ai la version "R
> > version 2.15.3 (2013-03-01) ".
> > Merci pour votre réponse
> > Cordialement
> > faiza hamdi
> >

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Re: [Help-glpk] Help-glpk Digest, Vol 128, Issue 12

[xypron . glpk]

Bonjour Faiza,

j'espère que tu trouveras l'information necessaire sur

http://en.wikibooks.org/wiki/GLPK/Ruby#Rglpk

Cordialement

Heinrich Schuchardt

http://www.xypron.de

Am 22.07.13 um 10:26 schrieb Faiza Hamdi

> bonjour 
> je cherche à télécharger la fonction  "Rglpk_solve" 
> merci de me répondre
> cordialement
> faiza hamdi
> 


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Re: [Help-glpk] glpk multiple solutions from solver

[xypron . glpk]

Hello Chris,

you may need to switch off the presolver.

Best regards

Heinrich Schuchardt

http://www.xypron.de

Am 28.06.13 um 08:05 schrieb chris

> On Sat, Jun 15, 2013 at 9:57 PM, Michael Hennebry <
> 
> henne...@web.cs.ndsu.nodak.edu> wrote:
> 
> 
> 
> >  On Thu, 13 Jun 2013, chia jia wei wrote:
> 
> >
> 
> > On Wed, Jun 12, 2013 at 7:31 PM, Raniere Silva **
> 
> >> wrote:
> 
> >>
> 
> >>  In the case of solving the problem using glp_simplex, is there any way
> 
>  to
> 
>  retrieve the solution in between iterations?
> 
> 
> 
> >>>
> 
> >>> AFAIK, using glp_simplex it isn't possible. Take a look in chapter 4
> 
> >>> "Advanced
> 
> >>> API Routines" of the manual to some functions that can do that.
> 
> >>>
> 
> >>> Raniere
> 
> >>>
> 
> >>>
> 
> >> Do you have any simple example to illustrate the possibility of using the
> 
> >> advanced routines to achieve retrieving of multiple solutions?
> 
> >>
> 
> >
> 
> > Look up callbacks.
> 
> >
> 
> > --
> 
> > Michael   henne...@web.cs.ndsu.nodak.edu
> 
> > "On Monday, I'm gonna have to tell my kindergarten class,
> 
> > whom I teach not to run with scissors,
> 
> > that my fiance ran me through with a broadsword."  --  Lily
> 
> 
> 
> 
> 
> Thanks for the advice.
> 
> I've tried to use the simplex algo to obtain an optimal basis.
> 
> Then, I made attached the callback listener,  implemented printout of
> 
> solution at GLP_IBINGO, and used glp_intopt but i seem to be getting
> 
> solutions that do not relate to the original problem data.
> 
> 
> 
> Regards,
> 
> chris

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Re: [Help-glpk] MathProg model processing error

[xypron . glpk]

Hello Robin,

you cannot have "and" in a constraint.

Use two constraints.

Best regards

Heinrich Schuchardt

http://www.xypron.de

Am 28.06.13 um 03:24 schrieb robin hankin

> hello, v4.51, macosx 10.8.3
> 
> 
> 
> 
> 
> 
> 
> Please help me,  I have a problem and have boiled it down to the following
> 
> .mod file which exibits the error I am struggling with:
> 
> 
> 
> wt118:~/Dropbox/glpk/alice_puzzle%
> 
> wt118:~/Dropbox/glpk/alice_puzzle% cat doesnotwork.mod
> 
> var x1, integer;
> 
> var x2, integer;
> 
> var x3, integer;
> 
> 
> 
> s.t. ss:   (x1 >= x2) and (x2 >= x3);
> 
> 
> 
> 
> 
> solve;
> 
> end;
> 
> wt118:~/Dropbox/glpk/alice_puzzle% glpsol -m doesnotwork.mod
> 
> GLPSOL: GLPK LP/MIP Solver, v4.51
> 
> Parameter(s) specified in the command line:
> 
>  -m doesnotwork.mod
> 
> Reading model section from doesnotwork.mod...
> 
> doesnotwork.mod:5: operand preceding >= has invalid type
> 
> Context: ...er ; var x2 , integer ; var x3 , integer ; s.t. ss : ( x1 >=
> 
> MathProg model processing error
> 
> wt118:~/Dropbox/glpk/alice_puzzle%
> 
> 
> 
> 
> 
> 
> 
> what is wrong with my doesnotwork.mod file?  What is wrong with my 'ss'
> 
> constraint?
> 
> 
> 
> thanks in advance
> 
> 
> 
> 
> 
> 
> 
> -- 
> 
> Robin Hankin
> 
> Uncertainty Analyst
> 
> hankin.ro...@gmail.com

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Re: [Help-glpk] [Fwd: GMPL table stmt]

[xypron . glpk]

> IM014:1:0:[Microsoft][ODBC Driver Manager] The specified DSN contains an
> 
> architecture mismatch between the Driver and Application

You are trying to use a 32bit DSN from a 64 bit executable or vice versa.

Make sure the bitness of the used components matches.

Best regards

Heinrich Schuchardt

http://www.xypron.de

Am 28.06.13 um 00:47 schrieb Andrew Makhorin

>  Forwarded Message 
> 
> From: technical forestry services 
> 
> To: bug-g...@gnu.org
> 
> Subject: GMPL table stmt
> 
> Date: Fri, 28 Jun 2013 10:06:35 +1200
> 
> 
> 
> Hello
> 
> 
> 
> I have been trying to get GMPL to read an SQLite3 database using the
> 
> following syntax.
> 
> 
> 
> set I ;
> 
> set J ;
> 
> set S dimen 2;
> 
> 
> 
> param c{i in I, j in J} ;
> 
> param d{i in I, j in J} ;
> 
> 
> 
> # table statement creates indexed parameters c[i, j] and d[i, j]
> 
> # and set S comprising (string) indices (i, j)
> 
> table tbl IN "iODBC"
> 
> 'DSN=SQLite3 Datasource'
> 
> 'SELECT id, srce, dest, dist, cost '
> 
> 'FROM Ytij':
> 
> S <- [srce, dest], d~dist, c~cost ;
> 
> 
> 
> data ;
> 
> set I := Seattle San-Diego ;
> 
> 
> 
> set J := New-York Chicago Topeka ;
> 
> end ;
> 
> 
> 
> There seems to be an issue with the table statement in that the code
> 
> will compile OK
> 
> and by adding GMPL printf and display statements will correctly list the
> 
> database contents
> 
> during the compile phase.  However during any Build phase I get the
> 
> following error message:
> 
> 
> 
> Reading tbl...
> 
> Failed to connect
> 
> 
> 
> The driver reported the following diagnostics whilst running
> 
> SQLDriverConnect
> 
> IM014:1:0:[Microsoft][ODBC Driver Manager] The specified DSN contains an
> 
> architecture mismatch between the Driver and Application
> 
> Test_glpk_sqlite3.mod:27: error on opening table tbl
> 
> MathProg model processing error
> 
> >Exit code: 1Time: 0.228
> 
>   
> 
> I have tried a couple of SQLite-ODBC drivers without success:
> 
> 1) sqliteodbc.exe available at www.ch-werner.de/sqliteodbc (installs
> 
> with (System) DSN=SQLite3 Datasource).
> 
> 2)sqlite odbc driver as part of SQLite2009 Pro Enterprise Manager
> 
> (installs with (System) DSN=DSN_SQLite2010Pro).  
> 
> SQLite2009 Pro Manager is available at
> 
> www.sqlite.org/cvstrac/wiki?p=ManagementTools   . 
> 
> 
> 
> Changing the driver has no effect as the same error is reported during
> 
> the Build phase.
> 
> 
> 
> I attach the database that I attempted to read from.
> 
> 
> 
> If you can shed any light on the issue I would be extremely grateful.
> 
> 
> 
> If you require further information don't hesitate to make contact.
> 
> 
> 
> Would you please acknowledge receipt of this E-mail.
> 
> 
> 
> Regards
> 
> 
> 
> LRB
> 
> 
> 
> ___
> 
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> 
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> 
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Re: [Help-glpk] glpk Limitation? Or what is the problem

[xypron . glpk]

Hello John,

error C005 is a memory access violation.

Best regards

Heinrich Schuchardt

http://www.xypron.de

Am 19.06.13 um 11:28 schrieb john tass

> Good morning,
> 
> I am trying to solve a large LP problem and I start my code (in C++) using
> 
> the following lines.
> 
> 
> 
> 
> 
> int C = 30;
> 
>  int H = 30;
> 
>  int R = 6;
> 
> 
> 
>  glp_prob *lp;
> 
>  int ia[1 + C*H*R + C*R], ja[1 + C*H*R + C*R];
> 
>  double ar[1 + C*H*R + C*R], z;
> 
> 
> 
>  cout<<"Basic matrices of LP problem are defined"<<"\n";
> 
> 
> 
>  lp = glp_create_prob();
> 
>  cout<<"lp problem created"<<"\n";
> 
>  glp_set_prob_name(lp, "sample");
> 
>  cout<<"Name of lp problem defined"<<"\n";
> 
>  glp_set_obj_dir(lp, GLP_MIN);
> 
>  cout<<"Direction of lp problem defined"<<"\n";
> 
> 
> 
> But something is wrong and I can not realize what it is. The program
> 
> interrupt as soon as it gets at line 9
> 
>  (cout<<"Basic matrices of LP problem are defined"<<"\n";) which is
> 
> executed fine. The problem occurs at the next line 10
> 
> (lp = glp_create_prob();)
> 
> and the program returns an error code like "3221225477". Is the problem
> 
> related to the size of LP problem?
> 
> Thanks for helping me
> 
> Ioannis Tassopoulos

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Re: [Help-glpk] Get a feasible solution with glpsol

[xypron . glpk]

Hello Esma,

start glpsol with --tmlim.

Or if using the library, call glp_ios_terminate in  the callback routine.

Best regards

Heinrich Schuchardt

http://www.xypron.de

Am 19.06.13 um 10:11 schrieb Mehiaoui

> Hello everybody,
> 
> 
> 
> Is it possible To stop the glpsol solver before terminating and get the best 
> solution (a feasible solution not the optimal one ) found so far ?
> 
> 
> 
> Thank you 
> 
> 
> 
> 
> 
> Esma
> 
> 
> 
> 
> 
> 
> 
> ___
> 
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> 
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> 
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Re: [Help-glpk] [Fwd: Need help running GLPK code in Ubuntu server]

[xypron . glpk]

Hello Kazi

GLPK for Java looks in /usr/include and /usr/local/include for glpk.h.

Best regards

Heinrich Schuchardt

http://www.xypron.de

Am 10.06.13 um 13:42 schrieb Kazi Moyeen ul Huq

> Hi,
> 
> Should usr/include contain a copy of glpk.h ? I don't have one. Should I
> 
> copy the glpk.h to usr/include or should I install another time ?
> 
> 
> 
> I installed glpk4.50 in the home directory. But, glpsol --version shows
> 
>  "GLPSOL: GLPK LP/MIP Solver, v4.50"
> 
> -Kazi
> 
> 
> 
> 
> 
> 
> 
> On Mon, Jun 10, 2013 at 3:26 AM,  wrote:
> 
> 
> 
> > Hello Kazi,
> 
> >
> 
> > glpk-4.50/src/glpk.h has no constyant LPX_LP. You obviously use a GLPK for
> 
> > Java built against an older include file.
> 
> >
> 
> > Check directory /usr/include.
> 
> >
> 
> > Best regards
> 
> >
> 
> > Heinrich Schuchardt
> 
> >
> 
> > http://www.xypron.de
> 
> >
> 
> > Am 09.06.13 um 21:54 schrieb Kazi Moyeen ul Huq
> 
> >
> 
> > > Hi,
> 
> > >
> 
> > > What is this Timer-0 error ?
> 
> > >
> 
> > > Thanks
> 
> > >
> 
> > > Kazi.
> 
> > >
> 
> > >
> 
> > >
> 
> > > ~/application/state-optimizer$ java
> 
> > -Djava.library.path=/usr/local/lib/jni/
> 
> > >
> 
> > > -classpath /usr/local/share/java/glpk-java.jar -jar st.jar
> 
> > >
> 
> > >
> 
> > >
> 
> > > Problem created ...test_MPC3
> 
> > >
> 
> > >
> 
> > >
> 
> > > *Exception in thread "Timer-0" java.lang.UnsatisfiedLinkError:
> 
> > >
> 
> > > org.gnu.glpk.GLPKJNI.LPX_LP_get()I*
> 
> > >
> 
> > > at org.gnu.glpk.GLPKJNI.LPX_LP_get(Native Method)
> 
> > >
> 
> > >  at org.gnu.glpk.GLPKConstants.(GLPKConstants.java:122)
> 
> > >
> 
> > > at
> 
> > >
> 
> > >
> 
> > org.totalgrid.reef.examples.stateoptimizer.DESDAlgorithm.optimize(DESDAlgorithm.java:145)
> 
> > >
> 
> > >  at
> 
> > >
> 
> > >
> 
> > org.totalgrid.reef.examples.stateoptimizer.StateOptimizerManager$1.run(StateOptimizerManager.java:65)
> 
> > >
> 
> > > at java.util.TimerThread.mainLoop(Timer.java:534)
> 
> > >
> 
> > >  at java.util.TimerThread.run(Timer.java:484)
> 
> > >
> 
> > >
> 
> > >
> 
> > >
> 
> > >
> 
> > >
> 
> > >
> 
> > > -Kazi
> 
> > >
> 
> > >
> 
> > >
> 
> > >
> 
> > >
> 
> > > On Sun, Jun 9, 2013 at 9:46 AM, Heinrich Schuchardt  
> > >wrote:
> 
> > >
> 
> > >
> 
> > >
> 
> > > > On 09.06.2013 15:33, Kazi Moyeen ul Huq wrote:
> 
> > >
> 
> > > >
> 
> > >
> 
> > > >> java -Djava.library.path=/usr/lib/**jni -jar st.jar
> 
> > >
> 
> > > >>
> 
> > >
> 
> > > >
> 
> > >
> 
> > > > Hello Kazi,
> 
> > >
> 
> > > >
> 
> > >
> 
> > > > the default installation path for GLPK and GLPK for Java is
> 
> > >
> 
> > > > /usr/local
> 
> > >
> 
> > > >
> 
> > >
> 
> > > > If you did not configure with --prefix the command line to execute you
> 
> > jar
> 
> > >
> 
> > > > file should be
> 
> > >
> 
> > > >
> 
> > >
> 
> > > > java -Djava.library.path=/usr/**local/lib/jni \
> 
> > >
> 
> > > >   -classpath /usr/local/share/java/glpk-**java.jar -jar st.jar
> 
> > >
> 
> > > >
> 
> > >
> 
> > > > Best regards
> 
> > >
> 
> > > >
> 
> > >
> 
> > > > Heinrich Schuchardt
> 
> > >
> 
> > > >
> 
> >

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Re: [Help-glpk] [Fwd: Need help running GLPK code in Ubuntu server]

[xypron . glpk]

Hello Kazi,

glpk-4.50/src/glpk.h has no constyant LPX_LP. You obviously use a GLPK for Java 
built against an older include file.

Check directory /usr/include.

Best regards

Heinrich Schuchardt

http://www.xypron.de

Am 09.06.13 um 21:54 schrieb Kazi Moyeen ul Huq

> Hi,
> 
> What is this Timer-0 error ?
> 
> Thanks
> 
> Kazi.
> 
> 
> 
> ~/application/state-optimizer$ java -Djava.library.path=/usr/local/lib/jni/
> 
> -classpath /usr/local/share/java/glpk-java.jar -jar st.jar
> 
> 
> 
> Problem created ...test_MPC3
> 
> 
> 
> *Exception in thread "Timer-0" java.lang.UnsatisfiedLinkError:
> 
> org.gnu.glpk.GLPKJNI.LPX_LP_get()I*
> 
> at org.gnu.glpk.GLPKJNI.LPX_LP_get(Native Method)
> 
>  at org.gnu.glpk.GLPKConstants.(GLPKConstants.java:122)
> 
> at
> 
> org.totalgrid.reef.examples.stateoptimizer.DESDAlgorithm.optimize(DESDAlgorithm.java:145)
> 
>  at
> 
> org.totalgrid.reef.examples.stateoptimizer.StateOptimizerManager$1.run(StateOptimizerManager.java:65)
> 
> at java.util.TimerThread.mainLoop(Timer.java:534)
> 
>  at java.util.TimerThread.run(Timer.java:484)
> 
> 
> 
> 
> 
> 
> 
> -Kazi
> 
> 
> 
> 
> 
> On Sun, Jun 9, 2013 at 9:46 AM, Heinrich Schuchardt wrote:
> 
> 
> 
> > On 09.06.2013 15:33, Kazi Moyeen ul Huq wrote:
> 
> >
> 
> >> java -Djava.library.path=/usr/lib/**jni -jar st.jar
> 
> >>
> 
> >
> 
> > Hello Kazi,
> 
> >
> 
> > the default installation path for GLPK and GLPK for Java is
> 
> > /usr/local
> 
> >
> 
> > If you did not configure with --prefix the command line to execute you jar
> 
> > file should be
> 
> >
> 
> > java -Djava.library.path=/usr/**local/lib/jni \
> 
> >   -classpath /usr/local/share/java/glpk-**java.jar -jar st.jar
> 
> >
> 
> > Best regards
> 
> >
> 
> > Heinrich Schuchardt
> 
> >

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Re: [Help-glpk] [Fwd: Need help running GLPK code in Ubuntu server]

[xypron . glpk]

Hello Kazi,

GLPK can also be build without GMP.

Try package libgmp3-dev.

Best regards

Heinrich Schuchardt

http://www.xypron.de

Am 08.06.13 um 19:55 schrieb Kazi Moyeen ul Huq

> Hi,
> 
> I tried to install the dependencies. Looks like the library "libgmp-dev "
> 
> isn't available for the "lucid" suite.
> 
> http://packages.ubuntu.com/search?keywords=libgmp-dev .
> 
> 
> 
> I installed all the other build-depends: debhelper, cdbs, libltdl-dev,
> 
> zlib1g-dev, libiodbc2-dev, libmysqlclient-dev, automake, autoconf, libtool.
> 
> "libgmp-dev" gave me the error msg -- E: Couldn't find package libgmp-dev.
> 
> 
> 
> Is there any work-around to that ? I'll try to install it from the other
> 
> suites ( precise) but I get a feeling from previous experience that the
> 
> server denies to install.
> 
> 
> 
> Thanks.
> 
> Kazi
> 
> 
> 
> 
> 
> On Fri, Jun 7, 2013 at 3:34 PM, Heinrich Schuchardt wrote:
> 
> 
> 
> > Hello Kazi,
> 
> >
> 
> >
> 
> > > When I used sudo apt-get install libglpk-java , the server installs
> 
> > > libglpk-java:  1.0.1-1.1. Then when I tried to run my program ( also
> 
> >
> 
> > You seem to be on an outdated version of Ubuntu (lucid). The current
> 
> > version is Ubuntu 12.04 LTS (Precise Pangolin).
> 
> >
> 
> > I suggest you uninstall GLPK and GLPK for Java on your Ubuntu server.
> 
> > sudo apt-get remove libglpk0 libglpk-dev
> 
> > sudo apt-get autoremove
> 
> >
> 
> > Install the build-depends: debhelper, cdbs, libgmp-dev, libltdl-dev,
> 
> > zlib1g-dev, libiodbc2-dev, libmysqlclient-dev, automake, autoconf, libtool
> 
> >
> 
> > Then build GLPK and GLPK for Java from source as described on
> 
> > http://glpk-java.sourceforge.**net/gettingStarted.html
> 
> >
> 
> > When you want to install with iODBC use this configure line for GLPK:
> 
> > configure --enable-dl --enable-odbc --enable-mysql --with-gmp
> 
> >
> 
> > If you prefer UnixODBC you will need unixodbc-dev instead of
> 
> > libiodbc2-dev, and may use this configuration line for GLPK:
> 
> >
> 
> > configure --enable-dl --enable-odbc=unix --enable-mysql --with-gmp
> 
> >
> 
> > Best regards
> 
> >
> 
> > Heinrich Schuchardt
> 
> >
> 
> >
> 
> >
> 
> > On 07.06.2013 16:41, Andrew Makhorin wrote:
> 
> >
> 
> >>  Forwarded Message 
> 
> >> From: Kazi Moyeen ul Huq
> 
> >> To: help-glpk@gnu.org
> 
> >> Subject: Need help running GLPK code in Ubuntu server
> 
> >> Date: Fri, 7 Jun 2013 08:41:41 -0400
> 
> >>
> 
> >> Hi,
> 
> >> I wrote a GLPK program in Windows-Java using the current vesrion of
> 
> >> GLPK-java (1.0.28). It works well in windows. Now, I have to port it to
> 
> >> a Ubuntu server. I'm an intermediate level Ubuntu user.
> 
> >>
> 
> >>
> 
> >> When I used sudo apt-get install libglpk-java , the server installs
> 
> >> libglpk-java:  1.0.1-1.1. Then when I tried to run my program ( also the
> 
> >> test program given in the glpk examples ) it gives the the message :
> 
> >>
> 
> >>
> 
> >> A. for  lp = GLPK.glp_create_prob();
> 
> >> Exception in thread "main" java.lang.**UnsatisfiedLinkError:
> 
> >> org.gnu.glpk.GLPKJNI.glp_**create_prob()J
> 
> >> at org.gnu.glpk.GLPKJNI.glp_**create_prob(Native Method)
> 
> >>
> 
> >>
> 
> >> B. forSystem.out.println(GLPK.glp_**version());
> 
> >> Exception in thread "main" java.lang.**UnsatisfiedLinkError:
> 
> >> org.gnu.glpk.GLPKJNI.glp_**version()Ljava/lang/String;
> 
> >>
> 
> >>
> 
> >>
> 
> >> Please suggest me what I should do next to make my program run in the
> 
> >> installed 1.0.1-1.1 version in server.( any modification required ? )
> 
> >>
> 
> >>
> 
> >>
> 
> >> Thanks in advance,
> 
> >> Moyeen
> 
> >>
> 
> >>
> 
> >> ==**===
> 
> >>
> 
> >> for further information, I also tried these:
> 
> >>
> 
> >> A. I tried to change the repository and install the 1.0.18-1
> 
> >> from  
> >> http://us.archive.ubuntu.com/**ubuntu/precise/universe
> >>  amd64
> 
> >> Packages instead of current " lucid/universe amd64 Packages" but the
> 
> >> server fails to install it. It says some dependencies can't be
> 
> >> installed.
> 
> >>
> 
> >>
> 
> >> B. similar thing happens when I tried to manually install by
> 
> >> using ./configure
> 
> >> then I received an error -
> 
> >> configure: error: glpk.h not found
> 
> >> The detail error message is attached.
> 
> >>
> 
> >>
> 
> >> ==**=
> 
> >>
> 
> >>
> 
> >>
> 
> >>
> 
> >>
> 
> >>
> 
> >>
> 
> >>
> 
> >> __**_
> 
> >> Help-glpk mailing list
> 
> >> Help-glpk@gnu.org
> 
> >> https://lists.gnu.org/mailman/**listinfo/help-glpk
> 
> >>
> 
> >
> 
> >

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Re: [Help-glpk] Problem Table OUT GLPK Excel

[xypron]

Bonjour Julien,

please, read
http://support.microsoft.com/kb/178717


The driver will not support DELETE, UPDATE, or ALTER TABLE statements. While
it is possible to update values, DELETE statements will not remove a row
from a table based on an Excel spreadsheet. These operations are not
supported. Basically, you can only append (insert) to a table. 


Cordialement

Heinrich Schuchardt



julien lecoq wrote:
> 
> Hi everybody,
> I started with GLPK and I have a problem with Excel.
> First, here is my test program :
>  /*Définition du paramètre B dans l'ensemble P*/param C {p in P};
> /*Définition du paramètre C dans l'ensemble P*/
> 
> table Test1 IN 'ODBC' /*Définition de la table d'importation Test1
> (qui peut avoir n'importe quel nom)*/   'DRIVER={Microsoft Excel Driver
> (*.xls)};dbq=.\Test.xlsx' /*Appel du driver Excel*/   'SELECT * FROM
> [Test1$]': /*Sélection de la feuille du fichier Excel*/P <- [Produit],
> B, C; /*Définition des paramètre à importer d'Excel*/
> 
> var D {p in P}; /*Définition de la variable D dans l'ensemble P*/var E
> {p in P}; /*Définition de la variable E dans l'ensemble P*/
> 
> s.t. c1 {p in P} : D[p] = B[p]; /*Contrainte pour recopier le
> paramètre B dans la variable D*/s.t. c2 {p in P} : E[p] = C[p];
> /*Contrainte pour recopier le paramètre C dans la variable E*/
> 
> solve; /*Appel du solver*/
> 
> table Test2 {p in P} OUT "ODBC" /*Définition de la table d'exportation
> Test1 (qui peut avoir n'importe quel nom)*/   'DRIVER={Microsoft Excel
> Driver (*.xls)};READONLY=FALSE; dbq=.\Test.xlsx' /*Appel du driver
> Excel*/   
>  
> /*Le . de .\Test.xlsx signifie que le fichier Excel est dans le même
> dossier que le fichier GLPK*/   'UPDATE [Test2$] set D = ;' /*Mise
> à jour de l'ensemble de la variable D de la feuille Test2*/   'UPDATE
> [Test2$] set E = ;' /*Mise à jour de l'ensemble de la variable E
> de la feuille Test2*/   'INSERT INTO [Test2$]' /*Insertion dans la
> feuille Test2*/   '(D,E)' /*Appel des variables à modifier*/  
> 'VALUES(?,?);': /*Nombre de valeurs à exporter, autant que de ?*/  
> D[p], E[p]; /*Définition des valeurs à exporter*/
> 
> end; /*Déclaration de fin de programme*/>
> It works fine but the "table OUT" makes a new lines in Excel everytimes I
> compile the program.
> I already tried DELETE FROM and WHERE .=. but I think I didn't write well.
> 
> Sorry for my English ... and thank you in advance.
> Regards,Loustic100
> 
> 
> 
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> 
> 

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Re: [Help-glpk] Installing glpk-java under mac os x

[xypron]

Hello,

please, provide the complete output of make.

Please, comment this line in swig/Makefile.in using "#":
#@HAVEMVN_TRUE@  $(MVN) clean package site

Then run
./configure && make && make check

Do you still get an error?

If you are using Maven for your project, please, see
http://glpk-java.sourceforge.net/index.html#Maven

Best regards

Heinrich Schuchardt


dirichlet-2 wrote:
> 
> Hi everyone,
> I do not know if this is the proper place to ask for help, but I'm trying
> to install GLPK under OS X Lion (10.7)
> I've installed GLPK version 4.50, then installed swig (I had to install
> Perl PCREV for it but it went fine), but I'm getting some errors when
> trying to install glpk-java from the source code, during the make command:
> 
> [ERROR]
> /Users/valerio/Desktop/cutimizer/cutimizer/lib/libglpk-java-1.0.27/swig/src/main/java/org/gnu/glpk/LPXKKT.java:[205,11]
> cannot find symbol
> [ERROR] symbol  : method
> LPXKKT_cs_ae_max_set(long,org.gnu.glpk.LPXKKT,double)
> [ERROR] location: class org.gnu.glpk.GLPKJNI
> [ERROR] -> [Help 1]
> [ERROR] 
> [ERROR] To see the full stack trace of the errors, re-run Maven with the
> -e switch.
> [ERROR] Re-run Maven using the -X switch to enable full debug logging.
> [ERROR] 
> [ERROR] For more information about the errors and possible solutions,
> please read the following articles:
> [ERROR] [Help 1]
> http://cwiki.apache.org/confluence/display/MAVEN/MojoFailureException
> make[2]: *** [all] Error 1
> make[1]: *** [all-recursive] Error 1
> make: *** [all] Error 2
> 
> 
> I get many errors like this, it appears that it cannot find the glpkjni
> interface, even though I configured it using the options specified in on
> the guide:
> ./configure \
> CPPFLAGS=-I/System/Library/Frameworks/JavaVM.framework/Headers \
> SWIGFLAGS=-I/System/Library/Frameworks/JavaVM.framework/Headers
> 
> what am I missing?
> 
> 

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[Help-glpk] GLPK for Windows 4.50, GLPK for Java 1.0.28

[xypron]

GLPK for Java 1.0.28 has been released. It is available from
http://glpk-java.sourceforge.net

GLPK for Windows 4.50 has been released. It is available from
http://winglpk.sourceforge.net
It includes 32bit and 64bit Windows executables of GLPK 4.50 and GLPK for
Java 1.0.28.

Best regards

Heinrich Schuchardt
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Re: [Help-glpk] MathProg time functions

[xypron . glpk]

Dear João,

GMPL provides time functions as described in the accompanying documentation of 
GLPK 4.49. What functionality are you missing?

Best regards

Heinrich Schuchardt

http://www.xypron.de

Am 08.05.13 um 16:02 schrieb João Flávio de Freitas Almeida

> Andrew,
>
> On AMPL we have ctime() and _solve_time to display current time and solver
>
> time respectively. As a suggestion, MathProg could have both functions also.
>
>
>
> Bests,
>
> João Flávio de Freitas Almeida
>
> ___
>
> Help-glpk mailing list
>
> Help-glpk@gnu.org
>
> https://lists.gnu.org/mailman/listinfo/help-glpk

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Re: [Help-glpk] [Fwd: Invalid MEX-file]

[xypron . glpk]

Hello Phillip,

as indicated on
http://sourceforge.net/projects/glpkmex/support?source=navbar
please contact one of the authors of GLPKMex for support.

Best regards

Heinrich Schuchardt

http://www.xypron.de

Am 07.05.13 um 20:00 schrieb Andrew Makhorin

>  Forwarded Message 
> Subject: Invalid MEX-file
> Date: Tue, 07 May 2013 15:43:18 +0200
>
> Hallo,
> i tried to use glpk with matlab but i have problem. I downloaded the
> file here http://glpkmex.sourceforge.net/
> and added the folder to matlab. Everytime i want to use the function "glpk"
> i get the error message:
>
> ??? Invalid MEX-file '...glpkmex\glpkcc.mexw64':
> ...glpkmex\glpkcc.mexw64 ist keine zulässige Win32-Anwendung.
> (it is not an allowed win 32 application)
>
> My matlab version: 7.9.0.529 (R2009b) 64-bit (win64) .
> I use Windows 7, 64-bit.
>
> Do you have any ideas? Thanks for your help.
>
>
>
>
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Re: [Help-glpk] forall and exists?

[xypron . glpk]

Hello Andrew,

GLPK is a linear programming solver. A constraint with an IF would not be 
linear.

In linear programming you might introduce binary variables for your purpose.

Or use a constraint programming solver.

Best regards

Heinrich Schuchardt

http://www.xypron.de

Am 07.05.13 um 07:48 schrieb Jay Hutfles

> Oh, I don't think there's anything wrong with them.  Well, except for how
> 
> I'm trying to use them.
> 
> 
> 
> I see that the examples only use them in computable parameters, though.  I
> 
> was trying to use them in constraints, and was getting errors along the
> 
> lines of "forall function does not exist" (sorry, I don't have the exact
> 
> error with me).  The constraints were of the form:
> 
> 
> 
>for all a in A, if x[a] =1 then there exists a b in B such that
> 
> (something or another based on a)
> 
> 
> 
> I was having trouble directly implementing constraints of this form, so I
> 
> changed the "if p then q" form to "not p or q" like this:
> 
> 
> 
>subject to C {a in A} :
> 
>   (1 - x[a]) + (if exists {b in B} (...something or other based on a..)
> 
> then 1 else 0) >= 1;
> 
> 
> 
> I'll have to try again in the morning when I'm more awake.  Thanks for the
> 
> guidance, Andrew.
> 
> 
> 
> 
> 
> 
> 
> On Mon, May 6, 2013 at 11:36 PM, Andrew Makhorin  wrote:
> 
> 
> 
> >
> 
> > > Can you provide a link to an example of each?  Any help would be
> 
> > > appreciated.
> 
> > >
> 
> >
> 
> > Please see glpk/examples/color.mod (for 'exists') and
> 
> > glpk/examples/egypt.mod (for 'forall').
> 
> >
> 
> > What is wrong with these operators?
> 
> >
> 
> >
> 
> >
> 
> ___
> 
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> 
> Help-glpk@gnu.org
> 
> https://lists.gnu.org/mailman/listinfo/help-glpk

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Re: [Help-glpk] GLPK for Java - problem - exception thrown for glp_find_col

[xypron . glpk]

Hello Andrew

> > The documentation leaves it unmentioned that the index is updated when
> 
> > a new column or row
> 
> > is added after calling glp_create_index.
> 
> 
> 
> On adding/removing named rows/columns the index is updated (if exists).
> 

Kindly add this information to the glp_create_index documentation. Otherwise a 
user might think he has to create a new index after a structural change of the 
problem.

Best regards

Heinrich Schuchardt

http://www.xypron.de

Am 02.05.13 um 13:48 schrieb Andrew Makhorin

> > please, update the documentation to clearly point out that an error is
> 
> > thrown in glp_find_col
> 
> > and glp_find row if not preceded by a call to glp_create_index.
> 
> 
> 
> Okay, I will add a paragraph to clarify the issue.
> 
> 
> 
> >  
> 
> > Wouldn't it be a good idea to let these functions implicitly call
> 
> > glp_create_index, if the
> 
> > index is missing?
> 
> 
> 
> I don't think so. It would be a sort of obscure feature, when the
> 
> program does something that it shouldn't do (if the feature is
> 
> disabled), and the user doesn't know about that.
> 
> 
> 
> >  
> 
> > The documentation leaves it unmentioned that the index is updated when
> 
> > a new column or row
> 
> > is added after calling glp_create_index.
> 
> 
> 
> On adding/removing named rows/columns the index is updated (if exists).
> 
> 
> 
> >  
> 
> > Why is the index not always created when creating a new problem? The
> 
> > overhead of the index seems to be negligible.
> 
> 
> 
> This feature is optional, because in most cases the name index is not
> 
> needed. If necessary, the user may easily enable this feature by a call
> 
> to glp_create_index immediately after glp_create_prob.

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Re: [Help-glpk] Fwd: Crash running the RELAX-IV algorithm

[xypron . glpk]

Hello Sylvain,

> Do you think there is a way to catch this kind of errors in the Java

http://www.cs.princeton.edu/~appel/papers/safejni.pdf
describes how the problem might be attacked.

But it seems that SafeJNI has not been developed any further. At least I could 
not find any download.

Best regards

Heinrich Schuchardt

http://www.xypron.de

Am 26.04.13 um 15:34 schrieb Sylvain Fournier

> Hello Heinrich,
>
>
>
> Do you think there is a way to catch this kind of errors in the Java
>
> wrapper in order to prevent the VM from crashing, or is this exception
>
> handling linked to the C code?
>
> I also noted that even if the new RELAX-IV algorithm is running without any
>
> error in Java, a GLPK constant may be missing: it would be
>
> GLPKConstants.GLP_JAVA_A_RC (the last parameter in the call to
>
> glp_mincost_relax4). Without this constant, I am using GLP_JAVA_V_PI but I
> 
> am not sure it is a stable workaround.
>
> Regards,
>
>
>
> --
>
> *Sylvain Fournier*
>
> Analista de Pesquisa Operacional
>
> *48 3239-2423*
>
> WPLEX Software Ltda.
>
> Rod SC 401 no. 8600 Corporate Park bloco 5 sala 101
>
> 88050-000 Santo Antônio de Lisboa, Florianópolis SC +55 48 3239-2400
>
> wplex.com.br
>
> [image: WPLEX]
>
>
>
>
>
> 
>
>
>
> -- Forwarded message --
>
> From: Sylvain Fournier 
>
> Date: 2013/4/25
>
> Subject: Crash running the RELAX-IV algorithm
>
> To: help-glpk@gnu.org
>
>
>
>
>
> Hello,
>
>
>
> I tried to run the new min cost flow algorithm (RELAX-IV) on a problem I
>
> have using glpk-java, and the java VM crashes (it doesn't catch the error)
>
> while the algorithm is processing.
>
> Using a regular C program, it also crashes:
>
> *** glibc detected *** ./run-relax4: free(): invalid next size (normal):
>
> 0x01cfb220 ***
>
> It seems to be a memory issue but I am not a C specialist.
>
>  I attach my problem in the dimacs format.
>
> The same problem runs without any problem using the old okalg, and I tried
>
> to run RELAX-IV on the sample.min example given in the graph documentation,
>
> which also works.
>
> Please let me know if I am doing something wrong.
>
>
>
> Regards,
>
>
>
> --
>
> *Sylvain Fournier*
>
>  Analista de Pesquisa Operacional
>
> *48 3239-2423*
>
> WPLEX Software Ltda.
>
> Rod SC 401 no. 8600 Corporate Park bloco 5 sala 101
>
> 88050-000 Santo Antônio de Lisboa, Florianópolis SC +55 48 3239-2400
>
> wplex.com.br
>
> [image: WPLEX]

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[Help-glpk] GLPK for Windows 4.49, GLPK for Java 1.0.25

[xypron]

GLPK for Java 1.0.25 has been released. It is available from
http://glpk-java.sourceforge.net

GLPK for Windows 4.49 has been released. It is available from
http://winglpk.sourceforge.net
It includes 32bit and 64bit Windows executables of GLPK 4.49 and GLPK for
Java 1.0.25.

Best regards

Heinrich Schuchardt
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Re: [Help-glpk] ELF Library

[xypron]

Hello Giorgio


Giorgio Sartor wrote:
> 
> However I successfully compiled the GLPK library in the server. Using
> "--prefix=PATH" with "configure" I was able to tell GLPK where to put my
> libraries.
> 

now use
export LD_LIBRARY_PATH=PATH
to make the library available.

See
http://tldp.org/HOWTO/Program-Library-HOWTO/shared-libraries.html#AEN80

Best regards

Heinrich Schuchardt
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Re: [Help-glpk] [Bug-glpk] glpk never terminates computation

[xypron . glpk]

Hello Anton,

>> LPX_K_MIPGAP
are you using the current version of GLPK: 4.48?

Best regards

Heinrich

Am 25.02.13 um 10:42 schrieb Anton Dimster

> Hi
>
>
>
> I am using glpk to solve a MIP problem, I am using the python binding
>
> provided by cvxopt.glpk.
>
>
>
> I have the following problem: I recently tried to solve a binary linear
>
> program, this is usually done quite rapidly, however the process is still
>
> running after 36 hours. I then tried set the LPX_K_MIPGAP to a higher level
>
> (0.06) and can see that in few seconds the search terminates, the message
>
> is
>
> "RELATIVE MIP GAP TOLERANCE REACHED; SEARCH TERMINATED"
>
>
>
> but the process never ends! and there is no way to access the solution.
>
>
>
> What can be the reason? I can only use glpk via python interface, so I do
>
> not know if there is a way to provide useful information/logs to solve this
>
> problem.
>
>
>
> Thanks for any hints.
>
> Anton
>
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>
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>
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Re: [Help-glpk] Performance decrease with more powerful computer

[xypron . glpk]

Hello Patrik

did you use a single thread benchmark?

Best regards

Heinrich

Gesendet mit der kostenlosen GMX iPhone App

Am 01.02.13 um 16:49 schrieb Patrik Dufresne

> Hi Reginald,
>
>
>
> Here are the hardware specs i'm comparing.
>
>
>
> System 1
>
> Windows XP SP2
>
> Intel Core i5 650 @ 3.20GHz 4 MB Cache
>
> 3GiB DDR3 1066/1333
>
> CPU mark (according to cpubenchmark.net) : 3154
>
> Total computation time : 331 sec
>
>
>
> System 2
>
> Windows XP SP2, Windows 7 64bits, Debian 64bits
>
> Core i7 CPU M 620 @ 2.67GHz 4M Cache
>
> 4GiB DDR3 1066
>
> CPU mark (according to cpubenchmark.net) : 2718
>
> Total computation time : 114 secs
>
>
>
> System 3
>
> Windows XP SP2, Debian 64bits
>
> *Core 2 Duo CPU E6550 @ 2.33GHz **4 MB** Cache L2
>
> *4GiB DDR2 800
>
> CPU mark (according to cpubenchmark.net) : 1493
>
> Total computation time : 172 secs
>
>
>
> I didn't run the benchmark on the computer it self, but the different
>
> between the number is big enough to expect better performance from System
>
> no 1 then System no 3. The total computation time of the problem on
>
> different platform for the same computer are almost identical. (less then
>
> 0.5 sec different). It's safe to assume the platform doesn't have any
>
> impact on the performance.
>
>
>
> I'm using GLPK 4.47 on every platform. On Linux, I did compile it from
>
> source with default flags. For Windows, I pick the pre-compiled version
>
> provided by winglpk project.
>
>
>
> To solve the problem, I need to run GLPK multiple time sequentially. I may
>
> provide dump of every instance of the problem.
>
>
>
> Patrik Dufresne
>
>
>
> On Fri, Feb 1, 2013 at 10:23 AM, Reginald Beardsley 
> wrote:
>
>
>
> > Could you  provide a few details?
>
> >
>
> > System configurations you're comparing?  GLPK version?  Compile time
>
> > options specified?
>
> >
>
> > There are a huge number of possibilities.  Why do you think the computer
>
> > is "more powerful"?
>
> >
>
> > Reg
>
> >
>
> >
>
> >
>
> > --- On *Fri, 2/1/13, Patrik Dufresne * wrote:
>
> >
>
> >
>
> > From: Patrik Dufresne 
>
> > Subject: [Help-glpk] Performance decrease with more powerful computer
>
> > To: "GLPK help" 
>
> > Date: Friday, February 1, 2013, 8:56 AM
>
> >
>
> >
>
> > Hi,
>
> >
> 
> > I'm using GLPK in one project and the time taken to compute is longer on a
>
> > more powerful computer. Does it make any sense to you ?
>
> >
>
> > I don't have any clues about how to debug it. I would really appreciate
>
> > tips to diagnose the problem.
>
> >
>
> > Patrik Dufresne
>
> >
>
> > -Inline Attachment Follows-
>
> >
>
> > ___
>
> > Help-glpk mailing list
>
> > Help-glpk@gnu.org 
>
> > https://lists.gnu.org/mailman/listinfo/help-glpk
>
> >
>
> >
>
> > ___
>
> > Help-glpk mailing list
>
> > Help-glpk@gnu.org
>
> > https://lists.gnu.org/mailman/listinfo/help-glpk
>
> >
>
> >
>
> ___
>
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>
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>
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Re: [Help-glpk] java glpk

[xypron . glpk]

Hello David,

passing zero elements to the matrix only impairs the performance and not the 
result of the optimization.

Best regards

Heinrich Schuchardt

Gesendet mit der kostenlosen GMX iPhone App

Am 22.01.13 um 18:53 schrieb David Gabriel

> Hi,
>
> Thanks a lot for your continous support.
>
>
>
> I read in the documentation that is possible to pass 0 element to matrix.
>
> It will be easier for me to insert 0 in my matrix because I am writing my
>
> Linear problem dynamically (I set the parameters in java program) basing on
>
> inputs which always change .
>
> So I want to know if I keep these 0, my program will be wrong ?
>
>
>
> Thanks you.
>
>
> 
> 2013/1/15 Heinrich Schuchardt 
>
>
>
> > Hello David,
>
> >
>
> > keep care of the indexes used (e.g. calling GLPK.glp_set_col_kind).
>
> >
>
> > No need to pass zero elements of matrix.
>
> >
>
> > Memory assigned should be deleted.
>
> >
>
> > Integer problems are solved with glp_intopt.
>
> >
>
> > Cheers
>
> >
>
> > Heinrich
>
> >
>
> > package com.mycompany.mavenproject1;
>
> >
>
> > import org.gnu.glpk.GLPK;
>
> > import org.gnu.glpk.GLPKConstants;
>
> > import org.gnu.glpk.GlpkException;
>
> > import org.gnu.glpk.glp_iocp;
>
> > import org.gnu.glpk.glp_prob;
>
> > import org.gnu.glpk.SWIGTYPE_p_int;
>
> > import org.gnu.glpk.SWIGTYPE_p_double;
>
> >
>
> > /**
>
> >  * Hello world!
> 
> >  *
>
> >  */
>
> > public class App {
>
> >
>
> > public static void main(String[] args) {
>
> > /*
>
> >  * Minimize z = 0.5 x1 + 3 x2 + 2 x3 + 10 x4
>
> >  * Subject to
>
> >  * x1, x2, x3, x4 >= 0
>
> >  * x1, x2, x3, x4 are integers
>
> >  * x1 + 0.7 x2 = 4 //c1
>
> >  * x3 + 2 x2 >= 3 //c2
>
> >  * x4 + 2x1  >= 4 //c3
>
> >  */
>
> >
>
> > glp_prob lp;
>
> > glp_iocp iocp;
>
> > SWIGTYPE_p_int ind;
>
> > SWIGTYPE_p_double val;
>
> > int ret;
>
> > try {
>
> >
>
> > // Create problem
>
> > lp = GLPK.glp_create_prob();
>
> > System.out.println("Problem created");
>
> > GLPK.glp_set_prob_name(lp, "myProblem");
>
> >
>
> > // Define columns
>
> > GLPK.glp_add_cols(lp, 4);
>
> >
>
> > GLPK.glp_set_col_name(lp, 1, "x1");
>
> > GLPK.glp_set_col_kind(lp, 1, GLPKConstants.GLP_IV);
>
> > GLPK.glp_set_col_bnds(lp, 1, GLPKConstants.GLP_LO, 0, 0);
>
> >
>
> > GLPK.glp_set_col_name(lp, 2, "x2");
>
> > GLPK.glp_set_col_kind(lp, 2, GLPKConstants.GLP_IV);
>
> > GLPK.glp_set_col_bnds(lp, 2, GLPKConstants.GLP_LO, 0, 0);
>
> >
>
> > GLPK.glp_set_col_name(lp, 3, "x3");
>
> > GLPK.glp_set_col_kind(lp, 3, GLPKConstants.GLP_IV);
>
> > GLPK.glp_set_col_bnds(lp, 3, GLPKConstants.GLP_LO, 0, 0);
>
> >
>
> > GLPK.glp_set_col_name(lp, 4, "x4");
>
> > GLPK.glp_set_col_kind(lp, 4, GLPKConstants.GLP_IV);
>
> > GLPK.glp_set_col_bnds(lp, 4, GLPKConstants.GLP_LO, 0, 0);
>
> >
>
> > // Create constraints
>
> > GLPK.glp_add_rows(lp, 3);
>
> >
>
> > //x1 + 0.7 x2 = 4 //c1
>
> > GLPK.glp_set_row_name(lp, 1, "c1");
>
> > GLPK.glp_set_row_bnds(lp, 1, GLPKConstants.GLP_FX, 4, 4);
>
> >
>
> > //@TODO use correct length
>
> > ind = GLPK.new_intArray(3);
>
> > val = GLPK.new_doubleArray(3);
>
> >
>
> > GLPK.intArray_setitem(ind, 1, 1);
>
> > GLPK.doubleArray_setitem(val, 1, 1.0);
>
> > GLPK.intArray_setitem(ind, 2, 2);
>
> > GLPK.doubleArray_setitem(val, 2, 0.7);
>
> > GLPK.glp_set_mat_row(lp, 1, 2, ind, val);
>
> >
>
> > // x3 + 2 x2 >= 3 //c2
>
> > GLPK.glp_set_row_name(lp, 2, "c2");
>
> > GLPK.glp_set_row_bnds(lp, 2, GLPKConstants.GLP_LO, 3, 0);
>
> >
>
> > GLPK.intArray_setitem(ind, 1, 2);
>
> > GLPK.doubleArray_setitem(val, 1, 2);//x2
>
> > GLPK.intArray_setitem(ind, 2, 3);
>
> > GLPK.doubleArray_setitem(val, 2, 1);//x3
>
> > GLPK.glp_set_mat_row(lp, 2, 2, ind, val);
>
> >
>
> > //x4 + 2x1 >= 4 //c3
>
> > GLPK.glp_set_row_name(lp, 3, "c3");
>
> > GLPK.glp_set_row_bnds(lp, 3, GLPKConstants.GLP_LO, 4, 0);
>
> >
>
> > GLPK.intArray_setitem(ind, 1, 1);
>
> > GLPK.doubleArray_setitem(val, 2, 1);//x4
>
> > GLPK.intArray_setitem(ind, 2, 4);
>
> > GLPK.doubleArray_setitem(val, 1, 2);//x1
>
> > GLPK.glp_set_mat_row(lp, 3, 2, ind, val);
>
> >
>
> > // delete Arrays after usage
>
> > GLPK.delete_doubleArray(val);
>
> > GLPK.delete_intArray(ind);
>
> >
>
> > // Define objective
>
> > //Minimize z = 0.5 x1 + 3 x2 + 2 x3 + 10 x4
>
> > GLPK.glp_set_obj_name(lp, "z");

Re: [Help-glpk] [Fwd: GNU Program]

[xypron . glpk]

Hello Ali,

you forgot the
data;
statement.

Best regards

Heinrich



Am 18.01.13 um 19:48 schrieb Andrew Makhorin

>  Forwarded Message 
>
> From: Ali Raza 
>
> To: help-glpk@gnu.org
>
> Subject: GNU Program
>
> Date: Tue, 15 Jan 2013 17:44:24 -0500
>
>
>
> I have a quick question. I am trying to write a simple program in GNU
>
> software. I am having difficities and it is giving me errors. I have not
>
> used this program before and I would like to know if there is some help
>
> that is avaialable in guiding me to write the correct code. Would you
>
> please take a look at my code and let me know what am i doing wrong.
>
>
>
> Thanks
>
>
>
>
>
> var x >= 0;
>
> var y >= 0;
>
> param j = x;
>
> param k = y;
>
> param l :=   7.25 ;
>
> var x{1..n} integer;
>
> var y{1..m} integer;
>
> minimize obj: {(x/y) / (l)};
>
>
>
> param j : a  b  c   d   e   f   g   h
>
>   a 336 367 408 307 460 452 154 257
>
>   b 410 469 481 260 242 462 168 168
>
>   c 206 164 85 406 378 17 432 293
>
>   d 21 79 427 360 219 310 23 344
>
>   e 23 263 128 392 126 370 331 392
>
>   f 353 467 2 365 318 37 17 337
>
>   g 475 179 275 30 346 392 55 178
>
>   h 489 65 107 174 343 367 459 39
>
>
>
> param k : a 54
>
>   b 25
>
>   c 36
>
>   d 56
>
>   e 41  
>
>   f 45
>
>   g 26
>
>   h 14
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
> ___
>
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>
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>
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Re: [Help-glpk] [Fwd: Re: Help: How to build MIP model]

[Xypron]

Hello Matteo,

you are right that the GLPK API has some complexity, which a beginner 
may want to avoid.


The following C++ library tries to make creating the LP matrix entries 
easier:

http://sourceforge.net/projects/iajaarh/

More elaborate wrappers for GLPK may be found here:

Python:
http://pymprog.sourceforge.net/tutorial.html#a-dive-in-example
Java:
http://javailp.sourceforge.net/
http://www.xypron.de/projects/linopt/

Best regards

Heinrich Schuchardt



On 04.01.2013 20:31, Andrew Makhorin wrote:

 Forwarded Message 
From: Matteo Fischetti DEI
Subject: Re: [Help-glpk] Help: How to build MIP model
Date: Fri, 04 Jan 2013 15:43:34 +0100

Hi Andrew.

to easy writing a MIP model (in Cplex) using C, I wrote the trivial
functions below

 www.dei.unipd.it/~fisch/easy_lp.c

I do not know if you have something similar in GLPK, other than MathProg
of course, that could help beginners to write models with 1-index
variables (for 2-index var.s similar functions can be written)

Take care

--Matteo--


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Re: [Help-glpk] Linking error in AIX 6.1 for glpk 4.47

[Xypron]

On 30.12.2012 15:43, Souvik Sutradhar wrote:

ld: 0711-317 ERROR: Undefined symbol: ._glp_lpx_create_prob
ld: 0711-317 ERROR: Undefined symbol: ._glp_lpx_set_prob_name
ld: 0711-317 ERROR: Undefined symbol: ._glp_lpx_add_rows
ld: 0711-317 ERROR: Undefined symbol: ._glp_lpx_add_cols
ld: 0711-317 ERROR: Undefined symbol: ._glp_lpx_set_row_bnds
ld: 0711-317 ERROR: Undefined symbol: ._glp_lpx_set_col_name


Hello Souvik,

all symbols you are missing are deprecated.

Please, refer to the manual in glpk-4.47/doc/glpk.pdf. You should be
using
glp_create_prob instead of glp_lpx_create_prob,
glp_set_prob_name instead of glp_lpx_set_prob_name,
etc.

Best regards

Heinrich Schuchardt


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Re: [Help-glpk] Linking error in AIX 6.1 for glpk 4.47

[Xypron]

Hello Souvik,

when going through the default installation sequence you will not have 
to define any library path for the compiler. For gcc you would simply

add a parameter -lglpk to include the dynamic load library (libglpk.so).

How did you install GLPK? Did you run:
./configure
make
sudo make install
sudo ldconfig

Which compiler do you use (e.g. IBM XL C/C++ for AIX)?
What is the command line you used to compile and link your C++ program?

Best regards

Heinrich Schuchardt




On 29.12.2012 19:30, Souvik Sutradhar wrote:

Hi
I am trying to run a c++ program in IBM AIX 6.1, which is using glpk 4.47. The 
same program is running on SOLARIS, Linux and HP-UX platform. But when I am 
trying to run the program on AIX, compilation is successful but at the time of 
linking it is giveing the following error

ld: 0711-317 ERROR: Undefined symbol: ._glp_lpx_create_prob
ld: 0711-317 ERROR: Undefined symbol: ._glp_lpx_set_prob_name
ld: 0711-317 ERROR: Undefined symbol: ._glp_lpx_add_rows
ld: 0711-317 ERROR: Undefined symbol: ._glp_lpx_add_cols
ld: 0711-317 ERROR: Undefined symbol: ._glp_lpx_set_row_bnds
ld: 0711-317 ERROR: Undefined symbol: ._glp_lpx_set_col_name


I have included the library path of glpk and the libglpk.a library in link 
command.

Thanks&  Regards,



Souvik Sutradhar

Senior Software Engineer | Service Group



PS Srijan Tech Park, 4th Floor, DN-52, Salt Lake Sector V, Kolkata-700091, 
India.

T : +91-33-40134880 | M : +91-9836987928

E : souvik.sutrad...@ushacomm.com | W : www.ushacomm.com | Time Zone: GMT +5:30



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Re: [Help-glpk] Optimization and Multicore GLPK

[glpk xypron]

there is a loop over vector operations. The natural thing to do for these is 
> to
> use the SSE instructions to speed up the vector operations and spread the
> vectors over multiple cores.
> 
> Though conceptually simple, none of this is easy to do.  In addition,
> GLPK is easily the most complex code I've ever looked at in 20+ years of
> working on several million lines of scientific codes.  Fortunately, it's also
> hands down the best written large code I've ever seen which is a real
> delight.
> 
> Any optimization work on a code as sophisticated as GLPK is a major
> undertaking which will take a long time to execute.  The first step is 
> profiling
> and coverage analysis.
> 
> If there is sufficient interest in this subject, I propose to implement
> and document performance profiling and coverage analysis of GLPK in the
> wikibook using the various Netlib problem sets.  This will be for convenience
> restricted to the *nix environment.  However, it should generally be
> applicable to Windows if a *nix environment package such as Cygwin is used.  
> 
> I am particularly interested in comments from Andrew, Marc, Robbie and
> xypron.  All have been very generous to me in different ways and this is an
> attempt to repay them.  I come from a seismic processing background where run
> times are measured in tens of thousands of hours for a single dataset. 
> Fortunately, most seismic codes are trivially parallel. So a few hundred quad
> core nodes and a couple of weeks will get the job done.  Were that not the
> case, oil would be a lot more expensive than it is.  But we still do a lot
> of work to make the codes run faster.
> 
> Have Fun!
> Reg


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[Help-glpk] Tuning gcc compiled code with -mfpmath=both

[Xypron]

When compiling GLPK with GCC on a x86 architecture a performance gain of 
20 % can be gained by compiling with option -mfpmath=both.

This requires SSE to be enabled. This is default for the x86-64
compiler. For the 32bit compiler SSE has to be enabled by either of 
-march=, -msse, or -msse2.


-mfpmath=both allows both the FPU and the SSE registers to be
used. See
http://gcc.gnu.org/onlinedocs/gcc-4.7.1/gcc/i386-and-x86_002d64-Options.html

Hence I would compile GLPK with:

export CFLAGS="-march=native -O3 -pipe -mfpmath=both"
./configure --enable-dl --enable-mysql --enable-odbc
make -j8
make check
sudo make install
ldconfig

-march=native implies that the code may not be used on different CPUs.
-pipe reduces compile time by using pipes instead of files
-j8 reduces compile time by parallelization

Best regards

Heinrich Schuchardt

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Re: [Help-glpk] Multithreading/parallelization

[glpk xypron]

Hello Robbie,

> The new C standard, C11, supports multithreading
> natively:
have a look at http://sourceware.org/git/?p=glibc.git
There is no threads.h in the head version of the glibc library.

So GCC will not be able to support this feature.

Best regards

Heinrich Schuchardt

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Re: [Help-glpk] Multithreading/parallelization

[glpk xypron]

Hello Reg,

> A possible solution of particular interest is making each of the
> non-reentrant items an array indexed by thread number.  I won't know if that's
> possible until I read the code, but it might yield a very elegant solution. 
> Other possibilities will suggest themselves in due course once I understand
> the internal structure.
On Linux pthread_t is of type unsigned long long (0 .. 2^32-1).
On my 1GB Debian system 
/proc/sys/kernel/threads-max = 15849
but the thread id often has higher values.
threads-max may be > 70 depending on memory size.
On Windows the number of concurrent threads can be greater than 5.
So a simple array indexed by thread number will probably not be a viable choice.

Best regards

Heinrich Schuchardt

 Original-Nachricht 
> Datum: Sat, 15 Dec 2012 06:57:42 -0800 (PST)
> Von: Reginald Beardsley 
> An: glpk 
> Betreff: Re: [Help-glpk] Multithreading/parallelization

> 
> While we wait to hear from Andrew, I made a quick assessment.  glpk is
> under 100k lines w/ under 600 static declarations in the src directory.  I did
> not look in the w32 & w64 directories.
> 
> I consider that large, but comfortable.  Particularly when I take into
> account the high quality of the code.  I've found myself the sole support for
> much larger codes that were  poorly written by many hands.  Relative to
> past experience such as porting 500k lines of FORTRAN from VMS to Unix, this
> looks pretty simple.  I've also dealt w/ running old non-reentrant FORTRAN
> codes in a large seismic processing system by loading and unloading  named
> COMMON in a wrapper so the FORTRAN codes did not require modification.  I
> don't have any experience w/ threads per se, but that's a minor detail
> relative to a project like this.
> 
> If Andrew is amenable to an attempt to make glpk multithreaded, I'll print
> the source and start reading code.  That will take some time, but it may
> save a lot of effort.  In particular I want to study the possible options
> for doing this w/ minimum effort.  The fact that the code is the work of a
> single, disciplined hand offers the possibility of this being rather less
> work than if many people had worked on it.
> 
> A possible solution of particular interest is making each of the
> non-reentrant items an array indexed by thread number.  I won't know if that's
> possible until I read the code, but it might yield a very elegant solution. 
> Other possibilities will suggest themselves in due course once I understand
> the internal structure.
> 
> For many years I supported the Seismic Unix package from the Center for
> Wave Phenomena at the Colorado School of Mines.  It's 360k+ lines w/ 400+
> programs written by many hands using key=value parameter input. A continual
> problem w/ that package was the lack of any error checking for typos.  I had
> made an experiment at fixing the problem, but never implemented it because
> it would have taken several months to modify all the programs in the
> package.  Then one day much later I woke up w/ an important insight into the
> calling structure of the package and did the entire job in under two hours 
> from
> start to finish.  Now unrecognized command line parameters are reported to
> the user, avoiding the user discovering the error after a long run when
> looking at the results.
> 
> In general, Harley's proposal seems to me the way to go.  That way if we
> get into trouble, it's easy to back up and start over.  If my idea about
> indexing by thread is viable, we'd actually just do the whole package in one
> go.  I'd like to keep the number of people working on this as small as
> practical. 2-3 is pretty much ideal, but certainly no more than 5.
> 
> However, the most important consideration is a good fit w/ Andrew's
> intentions and desires.  I wouldn't expect him to accept something like this
> until he'd seen it, but I don't want to start if he has a fundamental 
> objection
> to the project.
> 
> Have Fun!
> Reg
> 
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Re: [Help-glpk] Multithreading/parallelization

[glpk xypron]

Hello Harley,

you are right that multiple processes may run GLPK at the same time. But many
applications like Apache or Tomcat are multi threaded. So maybe you would
like to create a webservice offering route optimization by solving a TSP. You
wouldn't be able to do so with the current GLPK because Apache has multiple
threads per worker process, and you definitely do not want to shut down
Apache if one of the TSPs has a problem because a user of your webservice
came up with some strange input.

Best regards

Heinrich Schuchardt

 Original-Nachricht 
> Datum: Sun, 16 Dec 2012 00:43:26 +1100
> Betreff: Re: [Help-glpk] Multithreading/parallelization

> In the case of multiple LPs couldn't you just use the existing single
> threaded version and run separate instances of the application as I know
> members of this list already do? What is being gained by running this
> case with one instance of the application.
> 
> I am just trying to understand the different scenarios that need to be
> considered and I suspect that it will take a bit of time to understand
> all of the different use cases for multi threaded execution.
> 
> Harley

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Re: [Help-glpk] Multithreading/parallelization

[glpk xypron]

Hello Harley,

think of a multi threaded application that has multiple LPs to be solved at
once. Let one of the threads hit xerror or xassert. If you stick to only one
environment you will not be able to use the error hook function to gracefully
terminate this one thread. You will be forced to abort the whole application.

It is a different story if you only want to use multiple threads within
the MIP solver. In that case you might be able to stick to one environment.

Best regards

Heinrich Schuchardt

 Original-Nachricht 
> Datum: Sat, 15 Dec 2012 20:05:43 +1100
> Betreff: Re: [Help-glpk] Multithreading/parallelization

> Thanks for the comments.
> 
> Your point is very true about the environment structures as my item 2
> was meant to cover all of the data structures. However, I hadn't
> realised that this step was a lot larger than I had anticipated and
> there many dependent routines that also needed to be changed. I have
> only been basing my initial assessment on what needed to be done on the
> many discussions over the past few years. I havent engaged in any
> detailed assessment of the code yet.
> 
> Is it necessary to have multiple structures or could a single
> environment structure be used with controlled access to the single
> structure through the use of mutexes when accessed from multiple
> threads? I may be missing something fundamental here.
> 
> Also, I certainly definitely agree that for the code to move forward, we
> do need to do this work.
> 
> I shall gather any further comments and put together a more detailed
> work plan. 
> 
> Harley
> 
> On Sat, Dec 15, 2012, at 17:31, glpk xypron wrote:
> > Hello Harley,
> > 
> > GLPK not being threadsafe is hindering integration into other tools as
> > well as reducing solution speed for MIP problems.
> > 
> > The issue has been recurring for many years, and obviously is an issue
> > for enough users to deserve being fixed.
> > 
> > In your mail you indicated some necessary work steps. I see the
> following
> > additional work:
> > 
> > Currently GLPK has one environment structure which holds all memory
> > references and which is destroyed in case of an error. To make GLPK
> > thread safe it is necessary to have separate environment structures for
> > each instance of a the GLPK problem object (glp_prob). This has
> > implications on several API functions, e.g. glp_free_env,
> glp_error_hook,
> > glp_malloc. Furthermore all functions calling xerror or xassert will be
> > affected.
> > 
> > The effort needed is considerable and hence I appreciate your idea to
> > develop a solution in a community working environment. Before starting I
> > would be  interested to hear about Andrew's vision for GLPK.
> > 
> > Best regards
> > 
> > Heinrich Schuchardt

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Re: [Help-glpk] Multithreading/parallelization

[glpk xypron]

Hello Harley,

GLPK not being threadsafe is hindering integration into other tools as well as 
reducing solution speed for MIP problems.

The issue has been recurring for many years, and obviously is an issue for 
enough users to deserve being fixed.

In your mail you indicated some necessary work steps. I see the following 
additional work:

Currently GLPK has one environment structure which holds all memory references 
and which is destroyed in case of an error. To make GLPK thread safe it is 
necessary to have separate environment structures for each instance of a the 
GLPK problem object (glp_prob). This has implications on several API functions, 
e.g. glp_free_env, glp_error_hook, glp_malloc. Furthermore all functions 
calling xerror or xassert will be affected.

The effort needed is considerable and hence I appreciate your idea to develop a 
solution in a community working environment. Before starting I would be  
interested to hear about Andrew's vision for GLPK.

Best regards

Heinrich Schuchardt


 Original-Nachricht 
> Datum: Sat, 15 Dec 2012 12:45:14 +1100
> Von: Harley Mackenzie 
> An: help-glpk@gnu.org
> Betreff: Re: [Help-glpk] Multithreading/parallelization

> Hi Reginald
> 
> I was actually going through the same process of looking at the previous
> posts about developing a multi-threaded implementation of GLPK and was
> about to make a proposal for discussion about the future development of
> a multi-threaded version of GLPK.
> 
> From my investigation the two main libraries for the implementation of
> multi-threaded support for GLPK are the pthread library for linux
> systems and the pthread library for Windows that has been released under
> LPGL and is therefore compatible with the license of GLPK and could be
> included as part of the source with the appropriate inclusion of the
> license.
> 
> Thinking about a possible development path I would suggest a multi-stage
> approach so as to maintain compatibility with the existing version. The
> thinking is that the multi-threaded version would be an option during
> the build process until it was in a stable enough form that it could
> possibly become the default.
> 
> The development steps could be:
> 
>   1. Modify the make and autotools files to support the option of
>   multi-threaded compilation of GLPK with the appropriate linkage of the
>   correct pthread library for that platform with an option to activate
>   these features.
> 
>   2. Change the main non-reentrant data structures and dynamic memory
>   allocation routines with conditional compilation options so that
>   single-threaded compilation is un-affected.  
> 
>   3. Start the implementation of the multi-threaded versions of the MIP
>   branch and bound algorithms as I believe that these routines would be
>   the easiest to implement multi-threaded versions with the greatest
>   benefit with the most straight forward implementation. Again these
>   would all be conditionally compiled with the single or multi-threaded
>   compilation option.
> 
>   4. Implement multi-threaded implementation of the other solution
>   techniques where appropriate and can be feasibly implemented.
> 
> I am not an expert in multi-threaded C development or LP development but
> I am a very experienced programmer and have done a lot of C/C++ work in
> the past and developed multi-threaded applications in other languages. 
> 
> In terms of project management of the proposed development, it is
> important to understand that Andrew Makhorin is responsible for the
> development of GLPK and is, I believe, the only person with commit
> rights for the GLPK code. There hasnt been a new version of GLPK for
> some time and I dont know if Andrew has developments in the works that
> havent yet been released or whether he has any interest in the
> multi-threaded development of GLPK.
> 
> I certainly would like to do this within the existing project management
> of GLPK, but a possible way of coordinating the development of this
> relatively major change to the GLPK code would be to temporarily fork
> the project and host on GitHub where multiple participants could
> contribute to the project with a view to merging the changes back into
> the main GLPK source code at a later time. The GLPK wikibooks could be
> used for the documentation of the code and implementation with maybe a
> dedicated forum to discuss code design and implementation issues for
> this major task.
> 
> I am NOT suggesting a permanent forking of the code, just a temporary
> fork to facilitate community development of this major change to the
> GLPK code, with a view to merging back into the main GLPK code trunk at
> a later time.
> 
> I put this proposed plan up for discussion and would be interested to
> hear from members of the GLPK community who would like to participate,
> have different ideas about the management of the project or other
> comments.
> 
> Harley Mackenzie
> 

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Re: [Help-glpk] glpk.js

[glpk xypron]

Hello Henri,

your project sounds very interesting to me.

I saw that you translated part of the GLPK library to javascript.
Did you do so manually or with some machine translation tool?

Proper error handling with the GLPK library requires a hook function. How are 
errors handled in your javascript version?

The MIP solver provides a callback hook. Does this also exist in your library?

What is the significance of files grunt.js and package.json?

How would I use your library in a new project?

In README.md you write something about browser and server installation.
What is the overall architecture? Where will the library run - on the
server or in the browser?

Maybe you want to add an article on
http://en.wikibooks.org/wiki/GLPK

Best regards

Xypron




 Original-Nachricht 
> Datum: Mon, 10 Dec 2012 18:11:01 +0100
> Von: Henri Gourvest 
> An: help-glpk@gnu.org
> Betreff: [Help-glpk] glpk.js

> Hi,
> 
> I just started a new project to run glpk in a webbrowser in pure
> javascript.
> 
> https://github.com/hgourvest/glpk.js
> 
> actually I have LP/MIP solver running
> and the CPLEX parser
> 
> regards

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Re: [Help-glpk] Indexing a subset from 1..n

[glpk xypron]

Hello Joel,

param nPeriods := 12;
set Periods, default{1.. nPeriods};
# let even period be open
param FacilityOpen{p in Periods}, binary := if p mod 2 == 0 then 1 else 0;
set OpenPeriods:= setof{p in Periods: FacilityOpen[p] = 1}(p);
param nOpen := card(OpenPeriods);
set NOpen := {1..nOpen};
# beware this will take n^2 time
param pOpen{n in NOpen} := sum{p in OpenPeriods :
  n ==card(setof{i in OpenPeriods: i <=p }i) } p;
display pOpen;
end;

Best regards

Xypron
 Original-Nachricht 
> Datum: Wed, 28 Nov 2012 08:15:46 +1100
> Betreff: [Help-glpk] Indexing a subset from 1..n

> Hello all,
> I have a set of Periods from which I create the subset OpenPeriods when
> the facility is open.
> param nPeriods;set Periods, default{1.. nPeriods};param FacilityOpen{p in
> Periods}, binary;set OpenPeriods:= setof{p in Periods: FacilityOpen[p] = 1}
>  (p);
> The facility is not open during all periods and I have a constraint that
> considers the configuration of the facility the previous time it was open.
> So I am trying to index the set of OpenPeriods from 1...card(OpenPeriods)
> rather than with p but so far without any luck.
> Any help would be much appreciated.
> Thanks,
> Joel

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Re: [Help-glpk] MIP Solvers (i.e CBC, CPLEX, GLPK, GUROBI, LPSOLVE, SCIPC, SCIPL, SCIPS and XPRESS) Benchmark

[glpk xypron]

Hello Noli,

you are right that the GMPL interpreter has a value on its own.

Cf.
http://en.wikibooks.org/wiki/GLPK/Mixing_GLPK_with_other_solver_packages

Unfortunately the interfaces between GLPK-GMPL and other solvers tend
to be one time efforts without further maintenance.

Best regards

Xypron


 Original-Nachricht 
> Datum: Sun, 18 Nov 2012 17:53:38 +1100
> Betreff: [Help-glpk] MIP Solvers (i.e CBC, CPLEX, GLPK, GUROBI, LPSOLVE, 
> SCIPC, SCIPL, SCIPS and XPRESS) Benchmark

> Hi,
> 
> Have you seen this latest Mixed Integer Linear Programming Benchmark
> (MIPLIB2010) by Hans Mittelmann?
> 
> #
> 
>  3 Nov 2012 ===
> Mixed Integer Linear Programming Benchmark (MIPLIB2010)
> ===
>   H. Mittelmann (mittelm...@asu.edu)
> 
> #
> 
> http://plato.asu.edu/ftp/milpc.html
> 
> http://plato.asu.edu/bench.html
> 
> I wonder why GLPK is not scoring high in this benchmarking.
> 
> GLPK is actually quite fast / reasonable in solving my MIP models in
> Mac OS X (64 bit, 8 Gb, quad-core CPU, 2.4 Ghz) -- Macbookpro retina -
> base model.
> 
> CBC is not bad in this benchmarkiing.
> 
> https://projects.coin-or.org/Cbc
> 
> CBC is trying to use MathProg (GMPL) according to this posting
> (below), it is able to read MathProg / GMPL models but not reading
> back the results.
> 
> https://projects.coin-or.org/Cbc/ticket/108
> 
> It would be nice to have an alternative MIP solver for MathProg.
> 
> Thanks.
> 
> Noli
> 
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Re: [Help-glpk] A MathProg question

[glpk xypron]

Hello Reg,

sum{i in I} w[i]
is a linear function of w[i].

max{i in I} w[i]
is not a linear function of w[i].

GLPK can only solve linear problems.

You can still solve your problem as follows:

var w{i in I};
var obj;
minimize err: obj;
s.t. c{i in I} obj >= w[i];

Best regards

Xypron

 Original-Nachricht 
> Datum: Tue, 13 Nov 2012 05:54:03 -0800 (PST)
> Betreff: [Help-glpk] A MathProg question

> 
> 
> Why is:
> 
> minimize err : sum{i in I} w[i];
> 
> acceptable, but:
> 
> minimize err : max{i in I} w[i];
> 
> is not?
> 
> I can get the desired result by following example cf12b.mod, but I'm
> puzzled why glpsol 4.47 emits an error.  From reading the manual, I'd expect
> that any of the  iterated operators would be linguistically interchangeable w/
> sum.
> 
> Thanks,
> Reg
> 
> 
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Re: [Help-glpk] [Fwd: adding constraints incrementally]

[Xypron]

Dear Alreva,

your mail had to be forwarded manually because you are not subscribed to
the GLPK help list, cf.
https://lists.gnu.org/mailman/listinfo/help-glpk

The source distribution of GLPK is available at
ftp://ftp.gnu.org/gnu/glpk/glpk-4.47.tar.gz

In glpk-4.47/doc/glpk.pdf read the following chapters:
5.4 The cut pool routines
5.1.1 Using the callback routine

Best regards

Xypron

On 09.11.2012 10:48, Andrew Makhorin wrote:
>  Forwarded Message 
> To: Help-glpk@gnu.org
> Subject: [Help-glpk] adding constraints incrementally
> Date: Fri, 9 Nov 2012 00:57:10 -0800 (PST)
> 
> Dear all,
> I have a LP problem with a huge number of constraints which are saved into a
> large file. The problem is that I can't load this file into memory to use
> the constraints. I was thinking about using the cutting plane method in GLPK
> to solve the problem. However, I don't know whether it is possible to add
> constraints incrementally as cutting planes to a problem object, and perhaps
> remove some of them ? 
> Bests,
> Alreva


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Re: [Help-glpk] forall constraint in MathProg

[Xypron]

Hello Noli,

could you provide the condition you want to formulate in mathematical
notation?

"forall" is used for logical expression. Did you mean "sum"?
Instead of "p in 1..PERIOD" you may want to write "p in {1..PERIOD}".
If p is a number {pp in p} does not make sense.

Please, save the gmpl text below as test.mod, and run command.
glpsol -m test.mod --check --wlp test.lp

Check if test.lp contains the constraints you meant to write.

Best regards

Xypron

# file test.lp
param nperiod := 3;
param nnature := 20;
param nstand := 20;
set PERIOD := {1..nperiod};
set NATURE := {1..nnature};
set STAND := {1..nperiod};
param standarea {STAND} := 5 + 5 * Uniform01();
var forest{STAND, PERIOD};
var nh{NATURE, PERIOD};
s.t. habitat{p in PERIOD, n in NATURE, s in STAND} :
  sum{pp in PERIOD:pp <= p} forest[s, pp] + nh[n, p] = standarea[s];
end;


On 05.11.2012 19:29, Noli Sicad wrote:
> Hi,
>
> I am trying to translate this set of LINDO constraint (below) into
> MathProg. But I don't have any success.
>
> ##
>
> 37) S1P1 + N1P1 = 12.3
> 38) S1P1 + S1P2 + N1P2 = 12.3
> 39) S1P1 + S1P2 + S1P3 + N1P3 = 12.3
>
> 40) S2P1 + N2P1 = 35.6
> 41) S2P1 + S2P2 + N2P2 = 35.6
> 42) S2P1 + S2P2 + S2P3 + N2P3 = 34.6
>
> 43) S3P1 + N3P1 = 34.6
> 44) S3P1 + S3P2 + N3P2 = 34.6
> 45) S3P1 + S3P2 + S3P3 + N3P3 = 34.6
>
> .
> .
> .
>
> 94) S20P1 + N20P1 = 46.0
> 95) S20P1 + S20P2 + N20P2 = 46.0
> 96) S20P1 + S20P2 + S20P3 + N20P3 = 46.0
>
> ###
>
> I tried to implement like this:
>
> subject to Habitat_Constraint{ p in 1..PERIOD, n in 1..NATURE, s in STAND}:
>forall {pp in p} Forest[s,pp] + NH[n,p] = StandArea[s];
>
> However, I got this error below.
>
> ###
> Running tool: GLPK/MathProg
>
> GLPSOL: GLPK LP/MIP Solver, v4.47
> Parameter(s) specified in the command line:
>  --math Model_I_1_original_5-evenflow_even-acres_OF_alter3.mod
> Reading model section from
> Model_I_1_original_5-evenflow_even-acres_OF_alter3.mod...
> Model_I_1_original_5-evenflow_even-acres_OF_alter3.mod:77: domain
> expression has invalid type
> Context: ...ERIOD , n in 1 .. NATURE , s in STAND } : forall { pp in p }
> MathProg model processing error
>
> 
>
> Anybody knows how to do this set of constraint properly in MathProg properly?
>
> Any suggestions?
>
> Thanks.
>
> Regards,
>
> Noli
>
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Re: [Help-glpk] [Fwd: .run file equivalent in GLPK?]

[glpk xypron]

Hello Reg,

the following wiki pages are covering the same set of themes:

http://en.wikibooks.org/wiki/GLPK/Scripting_plus_MathProg
http://en.wikibooks.org/wiki/GLPK/Gnuplot
http://en.wikibooks.org/wiki/GLPK/Scalable_Vector_Graphics

May be you want to share your experiences here.

Best regards

Xypron

 Original-Nachricht 
> Datum: Sun, 4 Nov 2012 09:57:25 -0800 (PST)
> Betreff: Re: [Help-glpk] [Fwd: .run file equivalent in GLPK?]

> FWIW
> 
> I do a lot of the sort of thing Robbie described.
> 
> I have the basic model in a GMPL file w/ the data in a separate file.  I
> run a program that reads the raw data from several files to generate the
> GMPL data file.  I found that this worked much better than trying to read 2D &
> 3D arrays from .csv files.
> 
> It looks approximately like this:
> 
> #!/bin/sh
> 
> LIST=`/bin/ls data `
> 
> for I in ${LIST}
>do
> 
>myprog_1 data/${I} >job/${I}
> 
>glpsol -m job.mod -d job/${I} -o out/${I}
> 
>myprog_2 out/${I} >plot/${I}
> 
> done
> 
> In a *nix commandline environment (Solaris, BSD, Linux, MacOS X & Cygwin),
> the shell and awk can easily automate many tasks.  So no matter what
> you're using, this is a viable solution.  
> 
> I know a number of people who use Cygwin on Windows in preference to Linux
> because they have other software that is not available on Linux.  All the
> others have this available by default.
> 
> Reg
> 
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Re: [Help-glpk] order restrictions

[Xypron]

Hello Andrew,

glpk-4.47 came with a file glpk.pdf describing version 4.45.

Could you, please, update the manual to mention the minisat option of
glpsol.

Cnfsat.pdf describing addtional API functions should be merged as
additional chapter into glpk.pdf.

Best regards

Xypron

On 01.11.2012 15:27, Andrew Makhorin wrote:
>>> MIP optimzers are not fast solvers for constraint programming
>> problems.
>>
>> That's a shame.
>> What would you suggest for solving a 10x10x10 binary array subject to
>> ~200 restrictions?
>> It's not suitable for DLX.
>>
>> Also, I suspect that  any insights I have into my problems will not
>> improve on the T-D heuristic.
>>
> If your instance is pure 0-1 and all constraint coefficients are
> integer, you may try to solve it with the minisat solver supported by
> glpsol. You need to specify the '--minisat' option, in which case glpsol
> transforms your instance to a satisfiability problem and solves the
> latter with minisat. For more details please see the glpk reference
> manual. See also an example model (the "paint-by-numbers" puzzle) in the
> subdirectory glpk/examples/pbn.
>
>
>


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Re: [Help-glpk] Tomlin-Driebeek heuristic

[glpk xypron]

The URL to the article is:

http://opim.wharton.upenn.edu/~guignard/916_2011/papers_to_read/Driebeck_1966_MSc.pdf
 Original-Nachricht 
> Datum: Thu, 01 Nov 2012 07:54:35 +0100
> Von: "glpk xypron" 
> An: "Help Glpk" 
> Betreff: [Help-glpk] Tomlin-Driebeek heuristic

> Hello Andrew,
> 
> in GLPK you are refer to an author "Driebeck". In
> https://www.xypron.de/webdav/Heinrich/Literature/Linear_Programming/Branching/Driebeck_1966_MSc.pdf
> I find the author to be "Norman J. Driebeek".
> 
> @Article{RePEc:inm:ormnsc:v:12:y:1966:i:7:p:576-587,
>   author={Norman J. Driebeek},
>   title={An Algorithm for the Solution of Mixed Integer Programming
> Problems},
>   journal={Management Science},
>   year=1966,
>   volume={12},
>   number={7},
>   pages={576-587},
>   month={March},
> }
> 
> Could you, please check the spelling both in the coding and in the
> documentation.
> 
> Best regards
> 
> Xypron
> 
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[Help-glpk] Tomlin-Driebeek heuristic

[glpk xypron]

Hello Andrew,

in GLPK you are refer to an author "Driebeck". In
https://www.xypron.de/webdav/Heinrich/Literature/Linear_Programming/Branching/Driebeck_1966_MSc.pdf
I find the author to be "Norman J. Driebeek".

@Article{RePEc:inm:ormnsc:v:12:y:1966:i:7:p:576-587,
  author={Norman J. Driebeek},
  title={An Algorithm for the Solution of Mixed Integer Programming Problems},
  journal={Management Science},
  year=1966,
  volume={12},
  number={7},
  pages={576-587},
  month={March},
}

Could you, please check the spelling both in the coding and in the 
documentation.

Best regards

Xypron

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Re: [Help-glpk] order restrictions

[glpk xypron]

Hello Robin,

> I have a MIP, very similar to the sudoku.mod example in the examples/
> directory.
MIP optimzers are not fast solvers for constraint programming problems.

To choose the variable glpsol uses the Tomlin-Driebeek heuristic by default, cf.

http://opim.wharton.upenn.edu/~guignard/916_2011/papers_to_read/Driebeck_1966_MSc.pdf

and

*  Tomlin J.A. Branch and bound methods for integer and non-convex
*  programming, in J.Abadie (ed.), Integer and Nonlinear Programming,
*  North-Holland, Amsterdam, pp. 437-50 (1970).

You can influence the branching variable if you use GLPK library and provide a 
callback function. See
gpk-4.47/doc/glpk.pdf

Best regards

Xypron

 Original-Nachricht 
> Datum: Thu, 1 Nov 2012 11:20:24 +1300
> Von: robin hankin 
> An: help-glpk@gnu.org
> Betreff: [Help-glpk] order restrictions

> hello.
> 
> I have a MIP, very similar to the sudoku.mod example in the examples/
> directory.
> 
> It's a 3D binary array.
> 
> Let's say I have three restrictions, A, B, and C.
> 
> A is satisfied 70% of the time and it takes a long long time to evaluate.
> B is very similar to A but is satisfied 80% of the time.
> C is satisfied 0.0001% of the time and is very very quick.
> 
> A human would ignore A and B, and concentrate on C.  When he found a
> proposed solution
> that satisfies C, he would then check A and B (and if either of these is
> not satisfied he would
> go back to trawling through C).'
> 
> 
> How do I tell glpsol this information about the best order to evaluate
> A/B/C?  Or does it "know"?
> 
> 
> 
> 
> 
> 
> -- 
> Robin Hankin
> Uncertainty Analyst
> hankin.ro...@gmail.com

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Re: [Help-glpk] [Fwd: Read Excel data into subscripted set]

[Xypron]

Hello,

>> is there also a way to read two key columns, where the first consists
>> of elements of a set (let's call them element e1 from set S1) and fill
>> a subscripted set with the elements of the second column

The following solution will need O(n^2) time, where n is the number of
table lines:

set T, dimen 2;
set S1 := setof{(x,y) in T}x;
set S2{x in S1} := setof{(x,y) in T}y;
table t IN "CSV" "test.csv" :
T <- [x,y];
display S2;
end;

test.csv has the following content:

x,y
x1,y1
x1,y2
x3,y3
x4,y4

Best regards

Xypron



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Re: [Help-glpk] libglpk-java

[glpk xypron]

Hello Halim,

one reason for the behaviour you describe could be running multiple threads 
calling GLPK. GLPK is not thread safe. Is your application single threaded?

>> glp_error_hook error message
Do you mean GlpkException? How do you handle exceptions?

Could you, please, provide:
- version of GLPK for Java
- version of Cent OS
- version of Java runtime
- an example showing the problem

It is sufficient, if you send the example code to me (not the list).

Best regards

Xypron

 Original-Nachricht 
> Datum: Sun, 28 Oct 2012 18:04:25 +
> Betreff: [Help-glpk] libglpk-java

> Hello all,
> 
> I would like to know if there are folks happy with the libglpk-java
> llibrary binding.
> 
> I am now going through java system calls to C, with the C code calling the
> libglpk C library. The interface is via input and output files, which has
> worked very well, but I am looking for a full java solution (to avoid the
> file read/write).
> 
> On linux CentOS, libglpk-java has been unreliable. For the same problem, I
> get the right solution at times, a glp_error_hook error message at times,
> and no exception handling message at all at other times. Several of us have
> built the library from source on different machines, with the same overall
> experience.
> 
> Any success story with this library in the linux environment?
> 
> Thanks a bunch.
> 
> Rgds,
> halim
> 

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Re: [Help-glpk] [Fwd: Read Excel data into subscripted set]

[Xypron]

Hello Christian,

your mail had to be forwarded manually because you are not subscribed to
the GLPK help list.
See https://lists.gnu.org/mailman/listinfo/help-glpk

Two dimensional tables cannot be read by GMPL. Organize your data in
columns:
NUTR, FOOD, amt
Vitamin C, Hamburger, 0
Water, Wine, 0.93

glpk-4.47/doc/gmpl.pdf provides the syntax. GLPK for Windows has example
files in glpk-4.47/examples/sql.

Best regards

Xypron

On 26.10.2012 15:27, Andrew Makhorin wrote:
>  Forwarded Message 
> Subject: Read Excel data into subscripted set
> Date: Fri, 26 Oct 2012 14:46:44 +0200
>
> Hi,
>
> I have troubles with reading a 2-dimensional table in MS Excel and
> putting the data into a subscripted set. In a first step, I try to read
> a 2-dimensional table and fill its data into a 2-dimensional parameter.
> The example from the AMPL book pp.196-197 (can be found online:
> http://www.ampl.com/BOOK/CHAPTERS/13-tables.pdf) describes exactly this
> situation. It uses the diet problem to demonstrate, how the parameter
> amt (param amt {NUTR,FOOD} >= 0) can be read from MS Excel by 
> table dietAmts IN "ODBX" DIET2D.xls":
> [i ~ NUTR], {j in FOOD} ;
>
>
>
> Since the database connection in GMPL looks a little bit different, I
> adopted my working command for reading in the data of a 1-dimensional MS
> Excel table to the 2-dimensional case like that:
> table dietAmts IN 'ODBC'
>   'DRIVER={Microsoft Excel Driver (*.xls, *.xlsx, *.xlsm,
> *.xlsb)};dbq=.\test.xlsx'
>   'SELECT * FROM [Tabelle2$]' :
>   [i ~ NUTR], {j in FOOD} ;
>
> Putting everything together in one model file (why the table definition
> needs to be before the data part, I still do not understand..), Gusek
> gives me an error message:
> syntax error in field list
> Context:  , FOOD } >= 0 ; table dietAmts IN '...' '...' '...' : [ i ~
> MathProg model processing error
>
> I would appreciate every help!
>
> Regards,
> Christian
>
>
>
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Re: [Help-glpk] 200Mb of Tables - xmalloc error

[Xypron]

Hello Andrew,

for "0;" csv needs only two bytes. A double in C needs 8 bytes. Add pointers
in linked lists, memory for building the constraints in GMPL, memory for the
model in the GLPK library, and so forth. Yes reading the model into GMPL
will
need a whole lot more memory than your CSV file.

GLPK runs fine on 64bit. So you might just try on a bigger machine.

Given 200 Mb of raw data you may have to write a program that directly calls
the GLPK library. If you do not like C, there is a good choice of language
bindings available, see
http://en.wikibooks.org/wiki/GLPK

Best regards

Xypron

On 22.10.2012 21:49, Andrew B. Martin wrote:
> Hello,
>  
> I'm running a Windows XP 32bit with 1.95 Gb of RAM.
>  
> I'm am trying to build a model using .csv files, but am running out of
> memory (see xmalloc error below).
>  
> What is confusing me is that the combined size of the .csv files is no
> more than 200 Mb; when I hit Ctrl+Alt+Del and watch memory consumption
> in the 'performance' window CPU Usage does not crack 60% and PF Usage
> gets to 2.58 Gb when glpk stops building and the error pops up. It
> doesn't seem like a model of this size should exhaust my RAM, and the
> performance readings suggest it isn't. However, the error remains.
>  
> Does anyone have any suggestions as to why this might be happening?
>  
> Cheers,
> Andrew
>  
> GLPSOL: GLPK LP/MIP Solver 4.38
> Reading model section from 22_Oct_Model.mod...
> 318 lines were read
> Reading tab_Stands...
> Reading tab_Prescriptions...
> Reading tab_All_Stand_Types...
> Reading tab_Yield_Types...
> Reading tab_Ecodistricts...
> Reading tab_Mills...
> Reading tab_Segs...
> Reading tab_Tsheds...
> Reading tab_Ndrs...
> Reading tab_Excl...
> Reading tab_Buffer...
> Reading tab_Stand_Area...
> Reading tab_Stand_Age...
> Reading tab_Stand_Types...
> Reading tab_Stand_Types_Eco...
> Reading tab_Stand_Ecod...
> Reading tab_Stand_Tshed...
> Reading tab_Stand_Ndr...
> Reading tab_Stand_Buffer...
> Reading tab_Yields...
> xmalloc: no memory available
> Error detected in file ..\src\glplib07.c at line 72
>  
> This application has requested the Runtime to terminate it in an
> unusual way.
> Please contact the application's support team for more information.
> >Exit code: 3Time: 93.715
>
>
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Re: [Help-glpk] Printing non-zero parts of a solution matrix

[glpk xypron]

Hello Reg,

# Generate some random data.
set S := {1..1000};
param x{S} := if Uniform01() > .99 then Uniform01() else 0;
# Print nonzero elements only.
printf {s in S: x[s] > 0 }
  "x[%d] = %f\n", s, x[s];
end;

Best regards

Xypron
 Original-Nachricht 
> Datum: Fri, 19 Oct 2012 14:44:15 -0700 (PDT)
> Betreff: [Help-glpk] Printing non-zero parts of a solution matrix

> The problem I'm solving has a small number of non-zero results in the
> solution matrix.
> 
> Is there a way to print just the non-zero elements w/ GMPL?
> 
> The obvious approach of iterating over the matrix w/ for doesn't allow a
> conditional inside the actions.
> 
> thanks,
> Reg
> 
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Re: [Help-glpk] CSV buffer limits

[glpk xypron]

Hello Reginald,

in glpk-4.47/src/glpmpl06.c you find the following limitations:

#define CSV_FIELD_MAX 50
/* maximal number of fields in record */

#define CSV_FDLEN_MAX 100
/* maximal field length */

The following works:

# test1.mod writes csv
set I := {1..300};
set J := {1..20};
set K := {1..100};
param  x{I,J,K} := Uniform01();
table to {i in I, j in J, k in K} OUT "CSV" "test.csv" :
i, j, k, x[i,j,k];
end;

" test2.mod reads csv
set I, dimen 3;
param  x{I};
table ti IN "CSV" "test.csv" :
I <- [i,j,k], x;
printf "Number of values: %d\n", card(I);
printf "Average value: %f\n", (sum{(i,j,k) in I} x[i,j,k]) / card(I);
end;

Best regards

Xypron

 Original-Nachricht 
> Datum: Wed, 17 Oct 2012 10:03:28 -0700 (PDT)
> Betreff: [Help-glpk] CSV buffer limits

> Are there limits on the dimensions of .csv input and output in gmpl?  I
> don't see any mention of limits in the wiki or in the 4.45 gmpl.pdf file in
> the csv section, but I did notice a 100 character line length limit
> mentioned in the SQL section.  I'm working w/ 3D arrays on the order of 
> 300x20x100,
> so it would be easy to collide w/ buffer limits pretty much any way I
> organize the data.
> 
> Thanks,
> Reg
> 
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Re: [Help-glpk] Specifying a constraint in CPLEX notation

[glpk xypron]

Hello Reg,

which problems you can formulate does not depend on the input language to GLPK. 
Using the GMPL language would make writing the input file much easier. See 
glpk-4.47/doc/gmpl.pdf

> I want to constrain A[i] to be zero if all the B[i][j] in n are zero.
Checking if B[i][j] is zero will get you into trouble, if B[i,j] are not binary 
or integer. Would you consider 1E-30 as zero?

You will either have to introduce additional binary variables definining if 
B[i,j] is zero, or accept inaccuracies, e.g. in:

-M * sum{i in I, j in J} B[i,j] <= A[i] <= M * sum{i in I, j in J} B[i,j];

Best regards

Xypron

 Original-Nachricht 
> Datum: Wed, 3 Oct 2012 09:55:18 -0700 (PDT)
> Betreff: [Help-glpk] Specifying a constraint in CPLEX notation

> I'm doing basis pursuit using glpsol w/ input in CPLEX LP format. This has
> worked extremely well, but I decided to modify my problem formulation and
> have gotten myself into trouble. 
> 
> The new problem formulation is:
> 
> D[k] = sum(i in m)(A[i] + sum(j in n)( B[i][j]*S[j][k]))
> 
> where the A[i] & B[i][j] are unknowns.
> 
> I want to constrain A[i] to be zero if all the B[i][j] in n are zero.
> 
> A[i] is free
> B[i][j] >= 0
> 
> m < 10
> n < 300
> 
> Can I do this in CPLEX LP format or do I need to switch to another
> notation or C?   Are there any references on doing this?  
> 
> The closest thing I found was section 20.2 in the AMPL book, but I don't
> see how to apply that to my problem. I'm a geoscientist and a long way from
> home.  So even the obvious can be baffling to me.
> 
> Thanks,
> Reg
> 
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Re: [Help-glpk] Get number of columns from callback routine

[Xypron]

See the appendix for an example using the Driebeck Tomlin heuristic
implemented as callback function for branching down.

Best regards

Xypron

On 21.09.2012 19:16, Michael Hennebry wrote:
> On Fri, 21 Sep 2012, glpk xypron wrote:
>
>> for branching down on the most fractional variable you could use:
>
> I've read that that is not a particularly good criterion.
> That said, better criteria make more complex examples.
>



BranchDown.java.gz
Description: application/tgz
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Re: [Help-glpk] Get number of columns from callback routine

[glpk xypron]

Hello Patrik,

 for branching down on the most fractional variable you could use:

@Override
public void callback(glp_tree tree) {
int reason = GLPK.glp_ios_reason(tree);
if (reason == GLPKConstants.GLP_IBRANCH) {
glp_prob lp  = GLPK.glp_ios_get_prob(tree);
double n = GLPK.glp_get_num_cols(lp);
double frac = -1;
int ifrac = 0;
for (int i = 1; i <= n; i++) {
if (0 != GLPK.glp_ios_can_branch(tree, i)) {
double value = GLPK.glp_mip_col_val(lp, i);
if (frac <= value - Math.floor(value)) {
ifrac = i;
frac = value - Math.floor(value);
}
if (frac <= Math.ceil(value) - value) {
ifrac = i;
frac = Math.ceil(value) - value;
}
}
}
GLPK.glp_ios_branch_upon(tree, ifrac, GLPKConstants.GLP_DN_BRNCH);
}
}

Best regards

Xypron



 Original-Nachricht 
> Datum: Thu, 20 Sep 2012 13:37:43 -0400
> Von: Patrik Dufresne 
> An: help-glpk@gnu.org
> Betreff: [Help-glpk] Get number of columns from callback routine

> Hi,
> 
> I want to implement a simple always-down branching heuristic in GLPK. So I
> need to call the function glp_ios_can_branch() to check if the column is
> the right candidate for branching. But I'm wondering how to I determine
> the
> maximum number of column since my original problem may be changed by the
> pre-processor. Reading the documentation the following line should do it:
> 
> GLPK.glp_get_num_cols(GLPK.glp_ios_get_prob(tree));
> 
> Am I right ?
> 
> Thanks
> 
> Patrik Dufresne

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Re: [Help-glpk] Newbie questions encouraged?

[glpk xypron]

Hello Raj,

GLPK does not support multithreading.
You could run multiple programs in parallel that use GLPK.

Best regards

Xypron
 Original-Nachricht 
> Datum: Mon, 17 Sep 2012 09:23:44 +0530
> Von: "Raj Mathur (राज माथुर)" 
> An: "help-glpk@gnu.org" 
> Betreff: [Help-glpk] Newbie questions encouraged?

> Hi,
> 
> Does this list encourage (or at least tolerate) questions from rank 
> newbies, in both LP and GLPK?
> 
> To start off, is there any easy way to utilise all cores on a multi-CPU 
> machine through GLPK?  I.e. run a problem parallely in a multi-CPU 
> environment?
> 
> Regards,
> 
> -- Raj
> -- 
> Raj Mathur  || r...@kandalaya.org   || GPG:
> http://otheronepercent.blogspot.com || http://kandalaya.org || CC68
> It is the mind that moves   || http://schizoid.in   || D17F
> 
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Re: [Help-glpk] [Fwd: Trouble Linking with GLPK]

[glpk xypron]

Hello Erik,

your mail had to be forwarded manually because you are not a member of the GLPK 
help list, see
https://lists.gnu.org/mailman/listinfo/help-glpk

Take a look at
http://www.eyrie.org/~eagle/notes/rpath.html
http://www.wiredrevolution.com/system-administration/how-to-correctly-use-ld_library_path

Best regards

Xypron

>  Forwarded Message 
> From: Eric Anjie Guo 
> Date: Wed, 12 Sep 2012 10:30:46 -0400
> 
> Hi All,
> 
> 
> Sorry for the spam. I'm learning how to use GLPK, but seem to have
> trouble linking with the library.
> 
> 
> I compiled with the following command and there seems to be no problem:
> 
> 
> gcc -w -I$(CURDIR)/glpk-4.47/include -c sample.c -o sample.o
> 
> 
> And the following command was used for linking: (I installed GLPK
> at $(CURDIR)/glpk-4.47/)
> 
> 
> gcc -w -L$(CURDIR)/glpk-4.47/lib sample.o -lglpk -lm
> 
> 
> But when I run ./sample I get the following error message:
> 
> 
> ./sample: error while loading shared libraries: libglpk.so.0: cannot
> open shared object file: No such file or directory
> 
> 
> I've also tried linking with the static library by using:
> 
> 
> gcc -w -static -L$(CURDIR)/glpk-4.47/lib sample.o -lglpk -lm
> 
> 
> But the linkage was failed due to errors such as:
> 
> 
> sample.o: In function `main':
> sample.c:(.text+0xc): undefined reference to `glp_create_prob'
> sample.c:(.text+0x1e): undefined reference to `glp_set_prob_name'
> sample.c:(.text+0x2c): undefined reference to `glp_set_obj_dir'
> ...
> 
> 
> I'm working on SDSC Trestles: https://www.xsede.org/sdsc-trestles
> 
> 
> I would really appreciate it if anyone could help. Thank you so much!
> 
> 
> Best,
> Eric
> 
> 
> -- 
> Eric Guo, PhD Candidate
> School of Operations Research and Information Engineering
> 288 Rhodes Hall
> Cornell University
> Ithaca, NY 14850
> 
> ag...@cornell.edu
> http://www.orie.cornell.edu/
> 
> 
> 
> 
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Re: [Help-glpk] Aborting a long-running algorithm in GLPK

[glpk xypron]

Hello Marc,

in the callback function you can use glp_ios_terminate(tree) to stop the branch 
and bound search.

In the terminal listener or in the callback function you can use function 
glp_error to abort GLPK.

You should use glp_error_hook to safely exit glp_intopt.

This is the coding I use in GLPK for Java for this purpose:

...
jmp_buf glp_java_env;
if (setjmp(glp_java_env)) {
printf "function glp_intopt failed");
} else {
glp_error_hook(glp_java_error_hook, &glp_java_env);
glp_intopt(...);
}
glp_error_hook(NULL, NULL);
...

void glp_java_error_hook(void *in) {
/* free GLPK memory */
glp_free_env();
/* safely return */
longjmp(*((jmp_buf*)in), 1);
}

Best regards

Xypron


 Original-Nachricht 
> Datum: Mon, 10 Sep 2012 16:05:49 -0400
> Von: Marc Goetschalckx 
> An: GLPK help 
> Betreff: [Help-glpk] Aborting a long-running algorithm in GLPK

> Is there a way to safely signal a long running algorithm (glp_intopt) to 
> stop executing and clean up memory and to terminate operation from 
> outside the function call for the API.  This would be similar to 
> pressing CTRL+C during the operation of glpsol.  What I need is 
> different from setting the execution time limit before an long-running 
> operation has started.
> Thanks
> 
> -- 
> Marc Goetschalckx
> Industrial and Systems Engineering
> Georgia Institute of Technology, Atlanta, GA, USA
> 
> 
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Re: [Help-glpk] [Fwd: Specify initialization for MIP]

[glpk xypron]

Dear Ankit,

your message had to be forwarded manually, because you are not member of the 
GLPK help list, see
https://lists.gnu.org/mailman/listinfo/help-glpk

In glpk-4.47/doc/glpk.pdf, chapter 5 - Branch-and-Cut API Routines you will 
information about the usage of a callback function to specify a heuristic 
solution.

Best regards

Xypron

>  Forwarded Message 
> Subject: Specify initialization for MIP
> Date: Mon, 10 Sep 2012 02:10:56 +0530
> 
> Hi,
> I have been trying to solve MIP which contains around 1 integer 
> variables. Well, problem is very large so it is expected that glpk will 
> take infinitely huge amount of time. But also, I have good 
> initialization for the branch and bound technique used by MIP. Anyone 
> having any idea how to specify initialization for the MIP as couldn't 
> find in the user's guide ?
> 
> Thanks,
> regards,
> Ankit Gandhi
> 
> 
> 
> 
> 
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Re: [Help-glpk] Profiler for glpsol

[glpk xypron]

Hello Asma,

on Linux you can use oprofile to profile the glpk library:
http://oprofile.sourceforge.net

Best regards

Xypron
 Original-Nachricht 
> Datum: Fri, 7 Sep 2012 07:15:43 +0100 (BST)
> Von: esma mehiaoui 
> An: help-glpk@gnu.org
> Betreff: [Help-glpk] Profiler for glpsol

> 
> Hello, I would like to know if there are some profilers for glpsol
> ? Thank to you Asma

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Re: [Help-glpk] C API: Setting up a least-absolute-deviation

[glpk xypron]

Hello Jared,

you will have to keep the u[i] variables as columns in your problem.
And the objective will only have nonzereo coefficients w[i] for these
columns.

Have a look at http://www.xypron.de/projects/linopt/examples.html
to see how accessing the GLPK API can be eased by a wrapper.

Best regards

Xypron

 Original-Nachricht 
> Datum: Tue, 4 Sep 2012 17:39:54 -0700
> Von: Jared Miller 
> An: GLPK help 
> Betreff: Re: [Help-glpk] C API: Setting up a least-absolute-deviation

> Robbie,
> 
> Thanks for the reply. To clarify, I'm not asking for help with the basics
> of the C API (it looks pretty straightforward if your problem is in the
> right form); rather I'm asking how to translate my high-level formulation
> (which includes the dummy u[i]'s) into the low-level formulation (with only
> auxiliary and structural variables, objective only in terms of the structural,
> and all the bounds constant).
> 
> I'll try loading/translating my MathProg file into a "glp_prob" struct and
> examining the internal translation. Eventually I need to work on
> abstracting a way of getting problems of this type into the GLPK low-level 
> form.
> 
> On Sep 1, 2012, at 11:25 AM, Robbie Morrison wrote:
> 
> > 
> > Hello Jared
> > 
> > 
> > To:   help-glpk@gnu.org
> > Subject:  [Help-glpk] C API: Setting up a least-absolute-deviation
> > Message-ID:  <2f1bd370-dd45-45b3-af7e-6d41d9ccb...@gmail.com>
> > From: Jared Miller 
> > Date: Fri, 31 Aug 2012 15:52:11 -0700
> > 
> > 
> >> I have an absolute value objective function, minimizing
> >> the sum of abs( s[i] - x[i] ) for two vectors s and x,
> >> with the constraints given by Ax = b where A is a large
> >> but very sparse matrix.
> >> 
> >> So I'm using a dummy vector "u" in a MathProg model:
> >> 
> >>  minimize least_abs_dev: sum {i in I} (u[i]);
> >>  s.t. constr1{i in I} : b[i] = sum{j in I} (A[i,j] * x[j]);
> >>  s.t. constr2{i in I} : u[i] >= (s[i] - x[i]);
> >>  s.t. constr3{i in I} : u[i] >= -(s[i] - x[i]);
> >> 
> >> I also eventually want to incorporate weights into the
> >> objective:
> >> 
> >>  minimize least_abs_dev: sum {i in I} (u[i] * w[i]);
> >> 
> >> I've got this type of model working using MathProg
> >> and glpsol, but now I'm trying to figure out how to
> >> translate it to the strict form required by the C
> >> API.  Has anyone done this?  What's the best way to
> >> go about it?  I'm going to need high performance on
> >> some large problems.
> >> 
> >> I am fairly new to optimization and GLPK.  Any help
> >> would be much appreciated.
> >> 
> >> - JM
> > 
> > I'm not exactly sure what your question is, but here
> > are some observations base on my experiences.  I'm
> > going to assume C++ too.
> > 
> > First, there are some GLPK wikibook pages:
> > 
> >  http://en.wikibooks.org/wiki/GLPK/Using_the_GLPK_callable_library
> >  http://en.wikibooks.org/wiki/GLPK >> sections 14.1 thru 14.6
> > 
> > Second, you will probably need to understand how the
> > GLPK MathProg translator translates your high-level
> > model into a low-level problem -- unless you have some
> > other insights based on the theoretical formulation of
> > your problem.  One way of doing this is to formulate
> > simple instances of your model and examine the problem
> > in say CPLEX LP format.
> > 
> >  http://en.wikibooks.org/wiki/GLPK/Interoperability#CPLEX.C2.A0LP_format
> > 
> > I ended up writing a C++ class that interrogated the
> > GLPK problem object and produces an HTML table to view
> > in a web browser.  Detailed routine work which
> > invariably took several loops to get right.
> > 
> > Third, some kind of abstraction between your model
> > formulation and the raw GLPK calls could be useful.
> > One relatively simple example can be found here:
> > 
> >  http://en.wikibooks.org/wiki/GLPK/IAJAAR.H_project
> > 
> > I wrote a large class to provide a semi-intelligent
> > interface with GLPK.  This class tracked rows and
> > columns as they were added and performed integrity
> > checks too.  Then I had another abstraction above this
> > related to my domain modeling needs.  A background in
> > computer science can help here.
> > 
&

Re: [Help-glpk] financial compensation

[glpk xypron]

Hello Zvonko,

this is a pure LP problem:

# partners
set S;
# given flows;
set F, dimen 3;
# minimized flows
var f{S,S}, >=0;

minimize obj :
  sum{i in S, j in S} f[i,j];
  
s.t. c1{i in S} :
  sum{(j,i,x) in F} x - sum{(i,j,x) in F} x =
  sum{j in S} f[j,i]  - sum{j in S} f[i,j];

solve;

display f;

data;

set S := A B C;
set F :=
 A B 7000
 B C 5000
 C A 2000;
end;

Best regards

Xypron

 Original-Nachricht 
> Datum: Wed, 5 Sep 2012 08:13:18 +
> Von: Zvonko Bregar 
> An: "help-glpk@gnu.org" 
> Betreff: [Help-glpk] financial compensation

> Hello everyone,
> I came across a certain combinatorial problem.
> Of a mandatory debt compensation between firms.
> The problem can be stated as:
> You have a directed graph.
> Each vortex presents a firm (a company).
> Each (directed) link from A to B presents the money amount that the A-firm
> must pay to the B-firm.
> And the problem is to reduce all the redundant cycles,
> For example if A owes 7000 to B and B owes 5000 to C and C owes 2000 back
> to A then this cycle could be reduced by 2000 and the link between C and A
> becomes obsolete.
> My question is whether or not this problem can be formulated as a mixed
> integer linear program.
> If Yes, does it makes sense or it would be much better to apply some graph
> theory alghoritms for minimal trees, cycles etc.
> If it does make sense to apply MILP please point me to the literature.
> Thank you in advance
> Zvonko
> 
> OPOZORILO: To elektronsko sporo?ilo in vse njegove morebitne priloge lahko
> vsebujejo zaupne in/ali privilegirane informacije, ki so last
> Elektroin?tituta Milan Vidmar in so namenjene izklju?no naslovniku. ?e ste 
> sporo?ilo
> prejeli pomotoma zaradi napake v naslovu ali pri prenosu sporo?ila, Vas
> prosimo, da nas o tem obvestite s povratno po?to. V tem primeru vsebine
> prejetega sporo?ila ne smete uporabiti, kopirati, tiskati, objaviti ali
> distribuirati, ampak ga morate takoj uni?iti.
> 
> DISCLAIMER: This e-mail is for the intended recipient only. It contains
> proprietary information some or all of which may be legally privileged. If
> you received this e-mail by mistake please notify us by replying to this
> e-mail. Consequently, the contents of this e-mail must be deleted and not be
> used, copied, printed, disclosed or distributed.
> 

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Re: [Help-glpk] Parallelisation of MILP

[glpk xypron]

Hello Esma,

yes parallelization of MIP solving is possible and reportedly beneficial.

Different approaches exist, e.g.
- parallelization of the solution of the LPs of different nodes using
  the different cores of the CPU
  http://www-01.ibm.com/support/docview.wss?uid=swg21400049
- parallelization of the simplex algorithm making use of the CPU
  
http://web.njit.edu/all_topics/Prog_Lang_Docs/cplex80/doc/userman/html/moreUsing31.html
- parallelization of the simplex algorithm making use of the GPU
  http://homepages.laas.fr/elbaz/PCO11.pdf

GLPK is not threadsafe and hence cannot easily be used for parallelization.
Making GLPK threadsafe would require major design changes.

Best regards

Xypron

 Original-Nachricht 
> Datum: Tue, 4 Sep 2012 13:18:42 +0100 (BST)
> Betreff: [Help-glpk] Parallelisation of MILP

> Hello everyone, I would like to know if is it possible to parallelize the
> of an Mixed Integer Linear Program over a distributed architecture? Thank
> you in advanceAsma

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Re: [Help-glpk] different result

[Xypron]

Hello Ajeng,

you do not provide the excel solution. Hence it is impossible to tell if
it is valid.

glpsol has option -r to read a solution from a file.

Use command printf to calculate the right hand side of each constraint
and to check if it is met by the Excel solution.

Best regards

Xypron

On 02.09.2012 11:57, Ajeng Dewi Citra Langeni wrote:
> i already solve a problem with glpk, but i want to validate it with
> calculate the objective function in excel
> but i have the different value between objective function in glpk and
> excel.
> glpk's objective function was 1805582104 , but if i calculate it with
> excel it was 1838084829
> hereby i attached my problem, thanks in advance
>  
> warm regards
>
> Ajeng Dewi Citra Langeni
> Industrial Engineering
> Bandung Institute of Technology
>
>
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Re: [Help-glpk] C API: Setting up a least-absolute-deviation problem

[glpk xypron]

Hello Jared,

take a look at glpk-4.47/examples/sample.c

Best regards

Xypron

 Original-Nachricht 
> Datum: Fri, 31 Aug 2012 15:52:11 -0700
> Betreff: [Help-glpk] C API: Setting up a least-absolute-deviation problem

> 
> I have an absolute value objective function, minimizing the sum of abs(
> s[i] - x[i] ) for two vectors s and x, with the constraints given by Ax = b
> where A is a large but very sparse matrix.
> 
> So I'm using a dummy vector "u" in a MathProg model:
> 
>   minimize least_abs_dev: sum {i in I} (u[i]);
>   s.t. constr1{i in I} : b[i] = sum{j in I} (A[i,j] * x[j]);  
>   s.t. constr2{i in I} : u[i] >= (s[i] - x[i]);
>   s.t. constr3{i in I} : u[i] >= -(s[i] - x[i]);
> 
> I also eventually want to incorporate weights into the objective:
> 
>   minimize least_abs_dev: sum {i in I} (u[i] * w[i]);
> 
> I've got this type of model working using MathProg and glpsol, but now I'm
> trying to figure out how to translate it to the strict form required by
> the C API. Has anyone done this? What's the best way to go about it? I'm
> going to need high performance on some large problems.
> 
> I am fairly new to optimization and GLPK. Any help would be much
> appreciated.
> 
> - JM 

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Re: [Help-glpk] Concatenate Parameter "Fields" Question

[glpk xypron]

Hello Robert,

set DMD_t, dimen 4;
param Demand_t{DMD_t};
set DMD, dimen 3 := setof{(s, c, st, m) in DMD_t}(s, c & ", " & st, m);
param Demand{(s,cst,m) in DMD} := 
  sum{(s, c, st, m) in DMD_t: cst == c & ", " & st}Demand_t[s, c, st, m];
display DMD, Demand;
data;
set DMD_t :=
p1,'Dover',DE,1,
p2,'Dover',DE,1,
p2,'Tallahassee',FL,1,
p3,'Atlanta',GA,1,
p4,'Honolulu',HI,1,
p5,'Boise',ID,1,
p6,'Springfield',IL,1,
p7,'Indianapolis',IN,1,
p8,'Des Moines',IA,1;
param Demand_t :=
[p1,'Dover',DE,1]303,
[p2,'Dover',DE,1]697,
[p2,'Tallahassee',FL,1]236,
[p3,'Atlanta',GA,1]105,
[p4,'Honolulu',HI,1]163,
[p5,'Boise',ID,1]480,
[p6,'Springfield',IL,1]375,
[p7,'Indianapolis',IN,1]703,
[p8,'Des Moines',IA,1]775;
end;

Best regards

Xypron
 Original-Nachricht 
> Datum: Fri, 31 Aug 2012 00:45:44 -0500
> Betreff: [Help-glpk] Concatenate Parameter "Fields" Question

> I'm currently importing demand as a set of SKU(s), City(c ), State(s),
> TransMode(m) tuple parameters.  I'd like to eliminate a dimension by
> concatenating the City and State into one element.  I see how to do this for 
> a set:
> 
> set LOC := setof{(s, c, st, m) in DMD_t}(c&", "&st);  #the set of valid
> City/State combination
> 
> set DMD := setof{(s, c, st, m) in DMD_t}(s, c&", "&st, m);  #The demand
> set: SKU, City/State, Mode
> 
> Where DMD_t is my temporary demand set of imported data with dimension 4,
> and DMD is the 3 dimension set I'd like to work with in the model.
> 
> My question: Is there a similar construct for converting a 4-tuple
> parameter to a 3-tuple?
> 
> That is, can I somehow convert:
> Parameter Demand_t[s, c, st, m] to Parameter Demand[s, l, m] by
> concatenating the city and state dimenstions.
> 
> I realize I could concatenate the fields in my input data, but I'm curious
> if there is a way to accomplish this with parameter manipulation.  I'm new
> to glpk, so apologies in advance if this is a silly question.
> 
> Thanks for your help,
> Rob
> 

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Re: [Help-glpk] [Fwd: Implementation problems]

[glpk xypron]

Hello Sasch,

GLPK can solve linear optimization problems of type
min{ c^T x; A x <= b} 
Cf. http://en.wikipedia.org/wiki/Linear_programming

It is required that matrix A and vector b are constant.

You try to switch on and of some equations depending on a variable.
This is possible as follows:

s.t. c1{t in Zeiten, c in Krane, i in Aktionen[c]}
X[c,i] + M1 * b[c,i,t] >= x[c,t] >= X[c,i] - M2 * b[c,i,t];

Here b[c,i,t] are binary variables. Of cause you will need additional
constraints to force b[c,i,t] to model continuous time streams.

M1 and M2 should be chosen as small as possible.

abs() is a nonlinear function. Hence the following constraint cannot
exist in a linear program:
s.t. Sicherheitsabstand{c == "G", i in Aktionen, t in {S[i]..S[i]+P["g",i]}} : 
abs(x["K",t]-x["G",t]) >= D
Try to replace the constraint by two linear inequalities using a binary
variable describing if crane K is left or right of crane G.

Best regards

Xypron

 Original-Nachricht 
> Datum: Thu, 30 Aug 2012 23:10:39 +0200
> Betreff: Re: [Help-glpk] [Fwd: Implementation problems]

> Hello Xypron,
> 
> thank you for your prompt reply. I am afraid, that I can't follow
> completely. Can you elaborate?
> 
> Thank you
> Sascha
> 
> 
> 2012/8/30 glpk xypron 
> 
> > Hello Sascha,
> >
> > variables cannot be used to define which row of the problem exists.
> >
> > s.t. Position{c in Krane, i in Aktionen[c], t in
> > {S[c,i]..(S[c,i]+P[c,i])}} : x[c,t] = X[c,i];
> >
> > You could replace S[c,i] by binary variables and use a big M approach.
> >
> > Best regards
> >
> > Xypron
> >
> > >  Forwarded Message 
> > > Subject: Implementation problems
> > > Date: Thu, 30 Aug 2012 03:30:13 +0200
> > >
> > > Hi,
> > >
> > >
> > >
> > >
> > > I am trying to implement a model that is only given to me in a
> > > conceptual form in GUSEK using GLPK.
> > > When I try to solve the following model, I receive an error message
> > > concerning an operand with invalid type.
> > > I was wondering if someone could give me a pointer on how to fix this.
> I
> > > am rather new to GUSEK and GLPK
> > > and your help is highly appreciated.
> > >
> > >
> > > Kind regards.
> > >
> > >
> > >
> > >
> > > Model:
> > >
> > >
> > > set Krane;
> > > set Aktionen {c in Krane};
> > > set Zeiten;
> > >
> > >
> > > param P {c in Krane, i in Aktionen[c]};
> > > param D;
> > > param L;
> > > param X {c in Krane, i in Aktionen[c]};
> > > param V {c in Krane};
> > >
> > >
> > > var S {c in Krane, i in Aktionen[c]} >= 0, integer;
> > > var x {c in Krane, t in Zeiten} >= 0, integer;
> > >
> > >
> > > minimize z: sum{c in Krane} S[c,card(Aktionen[c])];
> > >
> > >
> > > s.t. Reihenfolge{c in Krane, i in {1..card(Aktionen[c])-1}} : S[c,i] +
> > > P[c,i] <= S[c,i+1];
> > > s.t. Position{c in Krane, i in Aktionen[c], t in
> > > {S[c,i]..(S[c,i]+P[c,i])}} : x[c,t] = X[c,i];
> > > s.t. Geschwindigkeit1{t in Zeiten, c in Krane} : x[c,t] - V[c] <=
> x[c,t
> > > +1]
> > > s.t. Geschwindigkeit2 {t in Zeiten, c in Krane} : x[c,t] + V[c] >=
> x[c,t
> > > +1]
> > > s.t. Sicherheitsabstand{c == "G", i in Aktionen, t in
> > > {S[i]..S[i]+P["g",i]}} : abs(x["K",t]-x["G",t]) >= D
> > > s.t. Startposition{c in Krane} : x[c,0] == X[c,0]
> > > s.t. max_Position{t in Zeiten, c in Krane} : x[c,t] <= L
> > > s.t. min_Position{t in Zeiten, c in Krane} : x[c,t] >= 0
> > >
> > >
> > >
> > >
> > >
> > >
> > > data;
> > >
> > >
> > > set Krane := "K" "G";
> > > set Aktionen :=
> > > "K" 1 2 3 4 5 6 7 8 9 10 11 12
> > > "G" 1 2 3 4 5 6 7 8 9 10 11 12;
> > > set Zeiten := {0..900}
> > > param P: 1 2 3 4 5 6 7 8 9 10 11 12:=
> > > "K" 20 20 20 20 20 20 20 20 20 20 20 20
> > > "G" 20 20 20 20 20 20 20 20 20 20 20 20;
> > > param D := 5;
> > > param L := 81;
> > > param X: 1 2 3 4 5 6 7 8 9 10 11 12:=
> > > "K" 2 10 9 14 9 14 9 3 80 6 40 2
> > > "G" 79 5 1 77 77 3 40 41 40 39 80 30;
> > > param V:=
> > > "K" (1/5)
> > > "G" (1/5);
> > > end;
> > >
> > >
> > > Error:
> > > GLPSOL: GLPK LP/MIP Solver, v4.45
> > > Parameter(s) specified in the command line:
> > >  --check --cover --clique --gomory --mir -m Dorndorf.mod
> > > Reading model section from Dorndorf.mod...
> > > Dorndorf.mod:26: operand preceding .. has invalid type
> > > Context: ...n { c in Krane , i in Aktionen [ c ] , t in { S [ c , i ]
> ..
> > > MathProg model processing error
> > > >Exit code: 1Time: 0.212
> > >
> > >
> > >
> > >
> > >
> > > ___
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> > > Help-glpk@gnu.org
> > > https://lists.gnu.org/mailman/listinfo/help-glpk
> >

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Re: [Help-glpk] [Fwd: Implementation problems]

[glpk xypron]

Hello Sascha,

variables cannot be used to define which row of the problem exists.

s.t. Position{c in Krane, i in Aktionen[c], t in
{S[c,i]..(S[c,i]+P[c,i])}} : x[c,t] = X[c,i];

You could replace S[c,i] by binary variables and use a big M approach.

Best regards

Xypron

>  Forwarded Message 
> Subject: Implementation problems
> Date: Thu, 30 Aug 2012 03:30:13 +0200
> 
> Hi,
> 
> 
> 
> 
> I am trying to implement a model that is only given to me in a
> conceptual form in GUSEK using GLPK.
> When I try to solve the following model, I receive an error message
> concerning an operand with invalid type.
> I was wondering if someone could give me a pointer on how to fix this. I
> am rather new to GUSEK and GLPK
> and your help is highly appreciated.
> 
> 
> Kind regards.
> 
> 
> 
> 
> Model:
> 
> 
> set Krane;
> set Aktionen {c in Krane};
> set Zeiten;
> 
> 
> param P {c in Krane, i in Aktionen[c]};
> param D; 
> param L;
> param X {c in Krane, i in Aktionen[c]};
> param V {c in Krane};
> 
> 
> var S {c in Krane, i in Aktionen[c]} >= 0, integer;
> var x {c in Krane, t in Zeiten} >= 0, integer;
> 
> 
> minimize z: sum{c in Krane} S[c,card(Aktionen[c])];
> 
> 
> s.t. Reihenfolge{c in Krane, i in {1..card(Aktionen[c])-1}} : S[c,i] +
> P[c,i] <= S[c,i+1];
> s.t. Position{c in Krane, i in Aktionen[c], t in
> {S[c,i]..(S[c,i]+P[c,i])}} : x[c,t] = X[c,i];
> s.t. Geschwindigkeit1{t in Zeiten, c in Krane} : x[c,t] - V[c] <= x[c,t
> +1]
> s.t. Geschwindigkeit2 {t in Zeiten, c in Krane} : x[c,t] + V[c] >= x[c,t
> +1]
> s.t. Sicherheitsabstand{c == "G", i in Aktionen, t in
> {S[i]..S[i]+P["g",i]}} : abs(x["K",t]-x["G",t]) >= D
> s.t. Startposition{c in Krane} : x[c,0] == X[c,0]
> s.t. max_Position{t in Zeiten, c in Krane} : x[c,t] <= L
> s.t. min_Position{t in Zeiten, c in Krane} : x[c,t] >= 0
> 
> 
> 
> 
> 
> 
> data;
> 
> 
> set Krane := "K" "G";
> set Aktionen := 
> "K" 1 2 3 4 5 6 7 8 9 10 11 12
> "G" 1 2 3 4 5 6 7 8 9 10 11 12;
> set Zeiten := {0..900}
> param P: 1 2 3 4 5 6 7 8 9 10 11 12:=
> "K" 20 20 20 20 20 20 20 20 20 20 20 20
> "G" 20 20 20 20 20 20 20 20 20 20 20 20;
> param D := 5;
> param L := 81;
> param X: 1 2 3 4 5 6 7 8 9 10 11 12:=
> "K" 2 10 9 14 9 14 9 3 80 6 40 2
> "G" 79 5 1 77 77 3 40 41 40 39 80 30;
> param V:=
> "K" (1/5)
> "G" (1/5);
> end;
> 
> 
> Error:
> GLPSOL: GLPK LP/MIP Solver, v4.45
> Parameter(s) specified in the command line:
>  --check --cover --clique --gomory --mir -m Dorndorf.mod
> Reading model section from Dorndorf.mod...
> Dorndorf.mod:26: operand preceding .. has invalid type
> Context: ...n { c in Krane , i in Aktionen [ c ] , t in { S [ c , i ] ..
> MathProg model processing error
> >Exit code: 1Time: 0.212
> 
> 
> 
> 
> 
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Re: [Help-glpk] Compiling GLPK project in Ubuntu / Linux (was --->no subject)

[glpk xypron]

Hello Antonio,

which version of Ubuntu do you use? See
http://www.ubuntu.com/download/desktop/upgrade
for upgrade information.

The current version is Ubuntu 12.04.1. LTS.

Package libglpk-dev contains version glpk.h for version 4.45 of GLPK.

File glpk.h only has the following include statements:
#include 
#include 

Best regards

Xypron



 Original-Nachricht 
> Datum: Sun, 26 Aug 2012 10:43:41 +1000
> Von: Noli Sicad 
> An: Antonio Carlos Moretti 
> CC: help-glpk@gnu.org
> Betreff: Re: [Help-glpk] Compiling GLPK project in Ubuntu / Linux (was
> --->no subject)

> Hi Antonio,
> 
> Whenever a post for help / request, please specify a subject matter.
> 
> > I installed GLPK as a package in UBUNTU.
> > I did exactly how is wrutten in
> > http://en.wikibooks.org/wiki/GLPK/Linux_packages
> >
> > When I tried to compile my file in C which calls the api routines I got
> a
> > message that "glpk.h:29:20: fatal error: glpios.h: No such file or
> > directory".
> >
> > Looks like gcc is not find the library.
> >
> > Could you please help me.
> 
> I think the ubuntu package only includes glpk.h, not all the glpk
> headers (i.e. include files) since it is binary package. You can
> verify this by looking at the /usr/include or /usr/local/include
> folder.
> 
> (BTW, the glpk include files in not present in Mac OS X gkpk install
> (usr/local/include folder. It is only glpk.h is installed. This is
> default binary install by glpk, I suppose).
> 
> I think you have to get the glpk-4.47 tarball and use the include
> files in /glpk-4.47/src/ folder for your glpk C project, if I am not
> mistaken.
> 
> I am not done any C glpk project, how others manage to have glpk-dev
> in their system?
> 
> Noli
> 
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Re: [Help-glpk] [Fwd: Re: [No Memory Available Error]]

[glpk xypron]

Hello Aly,

> DRIVER={Microsoft Excel Driver (*.xls)}

You want to use
DRIVER={Microsoft Excel Driver (*.xls, *.xlsx, *.xlsm, *.xlsb);

See
http://en.wikibooks.org/wiki/GLPK/ODBC#Microsoft_Excel

Please, subscribe to the GLPK help list, so Andrew does not have to
forward your mails manually, see
https://lists.gnu.org/mailman/listinfo/help-glpk

Best regards

Xypron

>  Forwarded Message 
> Subject: Re: [Help-glpk] [Fwd: No Memory Available Error]
> Date: Sat, 18 Aug 2012 08:31:16 -0400 (EDT)
> 
> Thanks a lot for your replies, Robbie and Xypron. I did understand your
> excellent remarks, but I still do have a couple of questions, please:
> 
> 1. So, I tried to use the 64 bit GLPK on a machine with windows 7 64 bit
> and Excel and Access 64 bit. However, when connecting to the Excel or
> the access database through ODBC, I get the following error:
> 
> "data source name not found and no default driver specified".
> 
> I use a .dsn file to connect to the database, and that has been working
> perfectly with the 32 bit GLPK. In that .dsn file, I have this written:
> 
> [ODBC]
> DRIVER={Microsoft Excel Driver (*.xls)}
> dbq=TestOne.xls
> 
> Any thoughts why this is not working, and how can I get it to work?
> 
> I understand Xypron's advice regarding switching my database to MySql. I
> could potentially do this in the future, but for now, I really need to
> connect to Excel and Access!
> 
> 2. I used to use CPLEX through generating the .lp or the .mps file
> through GLPK, then solve that using CPLEX. However, I was wondering if
> there is a way to automatically call CPLEX within the GLPK code (which
> would enable me to get the solutions from CPLEX back, and play with
> them,etc). I saw in one of the links that Robbie sent, a C code that
> apparently does this. Is there any other direct easier way to do that?
> 
> Your help will be greatly appreciated!
> 
> Best,
> Aly
> 

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Re: [Help-glpk] [Fwd: No Memory Available Error]

[glpk xypron]

Hello Aly,

a 32bit application can not address more than 2**32 bytes (4GB).

You can use the task manager to analyze which application is using how much 
memory.

Please, read
https://en.wikibooks.org/wiki/GLPK/ODBC#Machine_architecture

I suggest you put your data into a SQL data base like MySQL and use the 64bit 
version of GLPK.

Best regards

Xypron

>  Forwarded Message 
> Subject: No Memory Available Error
> Date: Wed, 15 Aug 2012 09:58:24 -0400 (EDT)
> 
> Hi guys,
> 
> I have two questions:
> 
> 
> I am trying to solve a model that I generate its data from Excel
> (connecting to it through ODBC). After the model is generated, glpk 
> terminates with
> a memory error. The message is:
> 
> glp_malloc: no memory available
> Error detercted in file ..\src\glpenv05.c at line 70.
> 
> Then, it terminates with a Microsoft Visual C++ Runtime Library runtime
> error.
> 
> I am using glpk 32 bit on a 64 bit windows 7 machine, and I use a 32 bit
> Excel. Any ideas how to get rid of this error? Seems like GLPK is not using
> all the available memory, since I also did solve the same model on a
> machine with 50 GB of Ram, and I still got the same error. Would using a 64 
> bit
> GLPK solve this? And in such case, would it work with the 32 bit Excel? or
> how could I force glpk in general to use all the available memory and solve
> this error?
> 
> 
> 2. Is there any way I can call CPLEX or Gurobi as the solver for the
> models I generate on GLPK?
> 
> Your help will be highly appreciated. Thanks a lot.
> Aly

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Re: [Help-glpk] verify equation

[glpk xypron]

Hello Sagor,

linear programming with GLPK can only minimize or maximize one term. So what
do you mean by

max(x+y,x'+y')

Do you want maximize the maximum of both terms (x+y and x'+y')?

Best regards

Xypron

 Original-Nachricht 
> Datum: Tue, 14 Aug 2012 22:55:49 -0700 (PDT)
> Betreff: [Help-glpk] verify equation

> Hi,
> 
> Is it possible to solve this equation using glpk?
> 
> max(x+y,x'+y')
> 
> x + x' = 1
> y + y' = 1
> variables are binary. It can only take 0 or 1. Maybe the constraints are
> not necessary.
> Can you please help  if the equations are correct? I am kind of new in
> linear programming
> and will appreciate the help.
> 
> Thanks
> Sagor

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Re: [Help-glpk] [Fwd: GLPK Implementation help]

[glpk xypron]

Hello João,

you would not add the glpk source folder if you have a library.

>> Error 1 error LNK2019: unresolved external symbol _glp_version referenced
This error means the your library path in the linker settings does not contain 
glpk_4_47.lib

Best regards

Xypron


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Re: [Help-glpk] [Fwd: glpsol not converging]

[glpk xypron]

Hello Andrew,

looking at the output Narendra provided GLPK is stuck in the warm up phase and 
cannot find an initial LP solution. Here the time limit of the mip solver is 
ignored.

Would it be possible to pass the tmlim parameter to the simplex solver?

@Narendra
Looking at the value of your objective function "obj =   3.241402100e+07" could 
it be that you have very large ratios between the smallest and largest matrix 
elements of your problem?

Please, start your model again without --check and provide start of the output, 
e.g.
Model has been successfully generated
GLPK Integer Optimizer, v4.47
289 rows, 480 columns, 1680 non-zeros
240 integer variables, all of which are binary
Preprocessing...
288 rows, 480 columns, 1440 non-zeros
240 integer variables, all of which are binary
Scaling...
 A: min|aij| =  1.000e+00  max|aij| =  1.500e+01  ratio =  1.500e+01
GM: min|aij| =  9.586e-01  max|aij| =  1.043e+00  ratio =  1.088e+00
EQ: min|aij| =  9.189e-01  max|aij| =  1.000e+00  ratio =  1.088e+00
2N: min|aij| =  9.375e-01  max|aij| =  1.000e+00  ratio =  1.067e+00
Constructing initial basis...
Size of triangular part = 286
Solving LP relaxation...
GLPK Simplex Optimizer, v4.47

The ratio provided in the scaling phase gives a good indication if your model 
is well conditioned.

Analyze your model whether you are using some big M approach or dummy costs 
with very high numbers and try to find a better scaled formulation.

Best regards

Xypron


 Original-Nachricht 
> Datum: Tue, 31 Jul 2012 16:41:40 -0700
> Betreff: Re: [Help-glpk] [Fwd: glpsol not converging]

> Hi Xypron,
> 
> Yes, I have re-checked the parameters again. I used 1 (10E5) and not
> 10E6 for --tmlim.
> 
> The last 10 lines of output from the run are:
> 
> |16587000: obj =   3.241402100e+07  infeas =  1.037e-09 (2)
> |16587500: obj =   3.241402100e+07  infeas =  7.363e-10 (2)
> |16588000: obj =   3.241402100e+07  infeas =  5.294e-10 (2)
> |16588500: obj =   3.241402100e+07  infeas =  6.339e-10 (2)
> |16589000: obj =   3.241402100e+07  infeas =  9.333e-10 (2)
> |16589500: obj =   3.241402100e+07  infeas =  1.177e-09 (2)
> |1659: obj =   3.241402100e+07  infeas =  3.791e-09 (2)
> |16590500: obj =   3.241402100e+07  infeas =  1.787e-09 (2)
> |16591000: obj =   3.241402100e+07  infeas =  8.604e-10 (2)
> |16591500: obj =   3.241402100e+07  infeas =  1.154e-09 (2)
> 
> This process is running on a 64-bit Linux m/c with 2G of memory reserved
> for this process. I also know that there is no slowdown happening because
> of any memory swapping etc. I am using v4.47 version as indicated by this
> message in the output of the run:
> 
> GLPSOL: GLPK LP/MIP Solver, v4.47
> 
> I also ran with --check option and the tool output is as below:
> 
> GLPSOL: GLPK LP/MIP Solver, v4.47
> Parameter(s) specified in the command line:
>  -m tam.mod -d step1.dat
>  --check
> Reading model section from tam.mod...
> 226 lines were read
> Reading data section from step1.dat...
> 2390 lines were read
> Generating IOSingleMode...
> Generating TotalInputIOs...
> Generating TotalOutputIOs...
> Generating IOPreInputMode...
> Generating IOPreOutputMode...
> Generating PreDefInput...
> Generating PreDefOutput...
> Generating UsedIOIsInput1...
> Generating UsedIOIsInput2...
> Generating UsedIOIsOutput1...
> Generating UsedIOIsOutput2...
> Generating InputIOUsedOnce...
> Generating OutputIOUsedOnce...
> Generating BlockInputIOUsedOnce...
> Generating BlockOutputIOUsedOnce...
> Generating FlatPreDefInput...
> Generating FlatPreDefOutput...
> Generating BlockInputFlatUnused...
> Generating BlockOutputFlatUnused...
> Generating FlatUsedIOIsInput...
> Generating FlatUsedIOIsOutput...
> Generating FlatBlockInputAssigned...
> Generating FlatBlockOutputAssigned...
> Generating FlatIOUsedOnceIn...
> Generating FlatIOUsedOnceOut...
> Generating FlatWireLengthIn...
> Generating FlatWireLengthOut...
> Generating WireLengthOut...
> Generating WireLengthIn...
> Generating WireLength...
> Generating Routing...
> Model has been successfully generated
> 
> I specified the --first option as I was trying different things to check
> if
> it helps in speeding up. I have also tried without that option, but I
> still
> get stuck in an endless run.
> 
> I really appreciate your help on this.
> 
> Thanks again and Best regards,
> -Narendra
> 
> 
> On Tue, Jul 31, 2012 at 4:22 PM, glpk xypron  wrote:
> 
> > Hello Narendra,
> >
> > if tmlim is 10 (10E5) the optimization should have stopped after 28
> > hours. Please, check you did not enter 100 (10E6).
> >
> > On Linux you can use
> > ps -df
> > to check the parameters of your running process.
> >
> > To be

Re: [Help-glpk] [Fwd: glpsol not converging]

[glpk xypron]

Hello Narendra,

if tmlim is 10 (10E5) the optimization should have stopped after 28 hours. 
Please, check you did not enter 100 (10E6).

On Linux you can use 
ps -df
to check the parameters of your running process.

To better understand your problem, please, provide:
- last output lines of your "endless" run
- operating system you run on (including whether its 32 or 64bit)
- version of GLPK you are using.
- output of glpsol -m tam.mod -d step1.dat --check

The parameter --first typically will slow down the solution. You should only 
specify it, if you are sure about how your variables are sorted and why you 
want to always branch on the first integer variable.

Best regards

Xypron


 Original-Nachricht 
> Datum: Tue, 31 Jul 2012 15:18:27 -0700
> Von: Narendra Devta-Prasanna 

> Betreff: Re: [Help-glpk] [Fwd: glpsol not converging]

> Hi Xypron, other Experts,
> 
> I have tried with a time limit of 10 and the run has been going on for
> the last 5 days with no end in sight. It has so far completed 16 million
> iterations with no converging in sight. And the obj value has remained the
> same since ~124000 iteration.
> 
> The options I used to run glpsol are:
> glpsol -m tam.mod -d step1.dat -o step1.out -y step1.res --first --cuts
> --tmlim 10 --mipgap 0.25
> 
> Can you please suggest to me what I can try to limit this and generate
> *some* solution even if it is not completely optimal but *close* enough.
> 
> Thanks and Regards,
> -Narendra
> 
> On Thu, Jul 26, 2012 at 3:19 PM, Xypron  wrote:
> 
> >  Hello Narendra,
> >
> >
> > >> + 34748: mip = not found yet >=   1.05880e+04(1; 0)
> > >> TIME LIMIT EXCEEDED; SEARCH TERMINATED
> >
> > you have to choose a time limit which is high enough to have a MIP
> > solution.
> >
> > Best regards
> >
> > Xypron
> >
> >
> > On 26.07.2012 23:40, Narendra Devta-Prasanna wrote:
> >
> > Hi Xypron,
> >
> > When I try with "--tmlim 100", the printf commands just print null
> strings
> > for the variables in the ILP. The output file does not have any values
> > assigned for the variables as well. In the end of the output file, I see
> > this:
> >
> > Integer feasibility conditions:
> >
> > KKT.PE: max.abs.err = 0.00e+00 on row 0
> > max.rel.err = 0.00e+00 on row 0
> > High quality
> >
> > KKT.PB: max.abs.err = 1.60e+01 on row 34
> > max.rel.err = 9.41e-01 on row 34
> > SOLUTION IS INFEASIBLE
> >
> > End of output
> >
> > The log file has this information:
> >
> > * 29500: obj =   1.058950243e+04  infeas =  2.460e-13 (2)
> > * 29725: obj =   1.05880e+04  infeas =  6.601e-13 (2)
> > OPTIMAL SOLUTION FOUND
> > Integer optimization begins...
> > + 29725: mip = not found yet >=  -inf(1; 0)
> > | 32500: obj =   1.05880e+04  infeas =  3.451e-10 (2)
> > | 33000: obj =   1.05880e+04  infeas =  4.318e-10 (2)
> > | 33500: obj =   1.05880e+04  infeas =  4.521e-10 (2)
> > | 34000: obj =   1.05880e+04  infeas =  5.004e-10 (2)
> > | 34500: obj =   1.05880e+04  infeas =  2.476e-10 (2)
> > | 34748: obj =   1.05880e+04  infeas =  4.083e-10 (2)
> > + 34748: mip = not found yet >=   1.05880e+04(1; 0)
> > + 34748: mip = not found yet >=   1.05880e+04(1; 0)
> > TIME LIMIT EXCEEDED; SEARCH TERMINATED
> > Time used:   120.8 secs
> > Memory used: 160.7 Mb (168467811 bytes)
> > Writing MIP solution to `./glpk_ex3/ex3_TAM_IP_glpk_step1.out'...
> >
> > Is it possible to print out the "OPTIMAL SOLUTION FOUND" in some way?
> The
> > actual routing problem I am solving is a non-linear problem which I am
> > modeling as a ILP to get a solution which is anyways not optimal for the
> > problem but happens to be much better than a "random" solution.
> >
> > So, for the ILP, even if it is not an optimal solution, it is acceptable
> > for my situation.
> >
> > Really appreciate your suggestions regarding this...
> >
> > Thanks & Regards,
> > -Narendra
> >
> >
> >

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Re: [Help-glpk] [Fwd: GLPK Implementation help]

[glpk xypron]

Hello João,

your mail had to be forwarded manually because you are not subscribed to the 
GLPK help list, cf.
https://lists.gnu.org/mailman/listinfo/help-glpk

Probably the library path is not correctly specified.
It worked for me as following on a 32bit Windows 7 system:

Download winglpk-4.47.1.zip from http://sourceforge.net/projects/winglpk/
Extract it and copy to c:\program files\glpk.
Copy glpk-4.47\w32\glpk_4_47.dll to C:\windows\system32.
Open Visual Studio Express 2010 C++.
Create new "Win32 Console Application"
Do not choose compiled headers.
Open project properties.
In "Linker->Additonal Dependencies" add
"c:\program files\glpk\glpk-4.47\w32\glpk_4_47.lib"
In "Configuration Properties->VC++ Directories add
c:\Program Files\GLPK\glpk-4.47\src
Enter the following code:

#include 
#include 
#include "glpk.h"
int main(int argc, char* argv[])
{
printf ("GLPK version %s\n", glp_version());
printf ("Press any key\n");
while (!kbhit()){}
getch();
return 0;
}

Press F5 to build and run.
On Windows 64bit adjust the pathes accordingly.

Best regards

Xypron

>  Forwarded Message 
> Subject: GLPK Implementation help
> Date: Tue, 31 Jul 2012 11:57:28 +0100
> 
> hi,
> 
> 
> I am João Guedes, master student of University of Minho, in Portugal. 
> I'm developing a LP tool for my thesis, and dicide to use GLPK as my
> solver, however i  am having some issues in the implementation
> I'm using MS Visual Studio 2010, and in my project i include your lib,
> and add your glpk.h to my addicionals c++ lib, but when i compile the
> program i have a error on linker in all your funcions like this error
> LNK2001: unresolved external symbol _glp_add_cols
> Can you please help me?
> 
> 
> The exemple that i'm trying to use is this:
> 
> 
> #include 
> #include 
> #include 
> 
> 
> int main(void)
> { glp_prob *lp;
>   int ia[1+1000], ja[1+1000];
>   double ar[1+1000], z, x1, x2, x3;
> lp = glp_create_prob();
> glp_set_prob_name(lp, "sample");
> glp_set_obj_dir(lp, GLP_MAX);
> glp_add_rows(lp, 3);
> glp_set_row_name(lp, 1, "p");
> glp_set_row_bnds(lp, 1, GLP_UP, 0.0, 100.0);
> glp_set_row_name(lp, 2, "q");
> glp_set_row_bnds(lp, 2, GLP_UP, 0.0, 600.0);
> glp_set_row_name(lp, 3, "r");
> glp_set_row_bnds(lp, 3, GLP_UP, 0.0, 300.0);
> glp_add_cols(lp, 3);
> glp_set_col_name(lp, 1, "x1");
> glp_set_col_bnds(lp, 1, GLP_LO, 0.0, 0.0);
> glp_set_obj_coef(lp, 1, 10.0);
> glp_set_col_name(lp, 2, "x2");
> glp_set_col_bnds(lp, 2, GLP_LO, 0.0, 0.0);
> glp_set_obj_coef(lp, 2, 6.0);
> glp_set_col_name(lp, 3, "x3");
> glp_set_col_bnds(lp, 3, GLP_LO, 0.0, 0.0);
> glp_set_obj_coef(lp, 3, 4.0);
> ia[1] = 1, ja[1] = 1, ar[1] =  1.0; /* a[1,1] =  1 */
> ia[2] = 1, ja[2] = 2, ar[2] =  1.0; /* a[1,2] =  1 */
> ia[3] = 1, ja[3] = 3, ar[3] =  1.0; /* a[1,3] =  1 */
> ia[4] = 2, ja[4] = 1, ar[4] = 10.0; /* a[2,1] = 10 */
> ia[5] = 3, ja[5] = 1, ar[5] =  2.0; /* a[3,1] =  2 */
> ia[6] = 2, ja[6] = 2, ar[6] =  4.0; /* a[2,2] =  4 */
> ia[7] = 3, ja[7] = 2, ar[7] =  2.0; /* a[3,2] =  2 */
> ia[8] = 2, ja[8] = 3, ar[8] =  5.0; /* a[2,3] =  5 */
> ia[9] = 3, ja[9] = 3, ar[9] =  6.0; /* a[3,3] =  6 */
> glp_load_matrix(lp, 9, ia, ja, ar);
> glp_simplex(lp, NULL);
> z = glp_get_obj_val(lp);
> x1 = glp_get_col_prim(lp, 1);
>  x2 = glp_get_col_prim(lp, 2);
> x3 = glp_get_col_prim(lp, 3);
> printf("\nz = %g; x1 = %g; x2 = %g; x3 = %g\n",
>  z, x1, x2, x3);
> glp_delete_prob(lp);
>   return 0;
> }
> 
> 
> 
> 
> 
> -- 
> Cumprimentos
> João Guedes
> 
> 
> 
> 
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Re: [Help-glpk] info

[Xypron]

Hello Daniele,

*  The routine ios_relative_gap computes the relative mip gap using the
*  formula:
*
* gap = |best_mip - best_bnd| / (|best_mip| + DBL_EPSILON)

Minimization example:
- Best integer solution 2
- Best bound -1.3
=> Gap = (2 - -1.3) / 2 = 1.65

If you called
glpsol --mipgap 1.7 -m problem.mod
the solver would stop with this soution.

Beware: The mip gap may rise while you solution gets better:

Integer optimization begins...
+   213: mip = not found yet <=  +inf(1; 0)
+   481: >>>>>  -4.0e+00 <=   7.0e+00 275.0% (10; 0)
+   875: >>>>>  -3.0e+00 <=   2.6e+00 186.7% (15; 3)
+  1215: >>>>>  -1.0e+00 <=   1.0e+00 200.0% (15; 11)
+  1397: mip =  -1.0e+00 <= tree is empty   0.0% (0; 47)
INTEGER OPTIMAL SOLUTION FOUND

The mip gap rose from 1.867 to 2. while the objective rose from -3 to -1
in this maximization problem.

Best regards

Xypron



On 30.07.2012 16:22, Daniele Micarelli wrote:
> hi
> I wanted to know more precisely what is the command: *mipgap tol*
>
>
> and the number that goes in place of tol to indicate precisely what is?
>
> thank you very much
>
>
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Re: [Help-glpk] Feasibility pump heuristic

[Xypron]

Hello Patrik,

glpios10.c has the following lines:
*  M.Fischetti, F.Glover, and A.Lodi. "The feasibility pump." Math.
*  Program., Ser. A 104, pp. 91-104 (2005). */
You can find the article at
http://www.dei.unipd.it/~fisch/papers/feasibility_pump.pdf

Further reading is:
http://www.dei.unipd.it/~fisch/papers/feasibility_pump_201.pdf
http://www.zib.de/Publications/Reports/ZR-05-42.pdf

Best regards

Xypron


On 26.07.2012 20:24, Robbie Morrison wrote:
> Hello Patrik
>
> 
> To:   help-glpk@gnu.org
> Subject:  [Help-glpk] Feasibility pump heuristic
> From: Patrik Dufresne 
> Date: Thu, 26 Jul 2012 12:51:55 -0400
> 
>
>> Hi,
>>
>> I'm using GLPK to model an integer linear problem and
>> then solve it using glp_intopt(). Since, I'm a beginner
>> with linear problem, I've try different option of the
>> solver. One of them is the Feasibility pump heuristic
>> (fp_heur). Enabling this option solve the problem
>> within 24sec instead of 192sec when disabled.
>>
>> My first question, do you have any reference material
>> to explain how the feasibility pump heuristic is
>> working ?
> This publication describes changes to GLPK 4.28 to test
> novel MILP branching techniques.  I don't know if it
> covers the heuristic you mentioned but it should
> provide some useful background:
>
>   Pryor, Jennifer; Chinneck, John W (2011), "Faster
>   integer-feasibility in mixed-integer linear
>   programs by branching to force change", Computers
>   and Operations Research 38 (8): 1143-1152,
>   doi:10.1016/j.cor.2010.10.025
>
> paywalled :
> http://www.sciencedirect.com/science/article/pii/S0305054810002546
> preprint  :
> http://www.sce.carleton.ca/faculty/chinneck/docs/PryorChinneck.pdf
>
>> When enabled, is the optimality is still garanteed ?
> Yes, barring unknown errors in chipset, compilers,
> libraries, and models.
>
> This might be of interest in relation to GLPK:
>
>   http://en.wikibooks.org/wiki/GLPK/Background_theory
>
> Then read up about the Karush-Kahn-Tucker (KKT)
> optimality conditions elsewhere:
>
>   http://en.wikipedia.org/wiki/Karush%E2%80%93Kuhn%E2%80%93Tucker_conditions
>
>> Thanks for you'r help.
>>
>> Patrik Dufresne
>> -- next part --
>> An HTML attachment was scrubbed...
>> URL:
> <http://lists.gnu.org/archive/html/help-glpk/attachments/20120726/ba56f1bc/attachment.html>
>
> HTH, Robbie
> ---
> Robbie Morrison
> PhD student -- policy-oriented energy system simulation
> Technical University of Berlin (TU-Berlin), Germany
> University email (redirected) : morri...@iet.tu-berlin.de
> Webmail (preferred)   : rob...@actrix.co.nz
> [from Webmail client]
>
>
>
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Re: [Help-glpk] [Fwd: glpsol not converging]

[Xypron]

Hello Narendra,

>> + 34748: mip = not found yet >=   1.05880e+04(1; 0)
>> TIME LIMIT EXCEEDED; SEARCH TERMINATED

you have to choose a time limit which is high enough to have a MIP solution.

Best regards

Xypron

On 26.07.2012 23:40, Narendra Devta-Prasanna wrote:
> Hi Xypron,
>
> When I try with "--tmlim 100", the printf commands just print null
> strings for the variables in the ILP. The output file does not have
> any values assigned for the variables as well. In the end of the
> output file, I see this:
>
> Integer feasibility conditions:
>
> KKT.PE <http://KKT.PE>: max.abs.err = 0.00e+00 on row 0
> max.rel.err = 0.00e+00 on row 0
> High quality
>
> KKT.PB: max.abs.err = 1.60e+01 on row 34
> max.rel.err = 9.41e-01 on row 34
> SOLUTION IS INFEASIBLE
>
> End of output
>
> The log file has this information:
>
> * 29500: obj =   1.058950243e+04  infeas =  2.460e-13 (2)
> * 29725: obj =   1.05880e+04  infeas =  6.601e-13 (2)
> OPTIMAL SOLUTION FOUND
> Integer optimization begins...
> + 29725: mip = not found yet >=  -inf(1; 0)
> | 32500: obj =   1.05880e+04  infeas =  3.451e-10 (2)
> | 33000: obj =   1.05880e+04  infeas =  4.318e-10 (2)
> | 33500: obj =   1.05880e+04  infeas =  4.521e-10 (2)
> | 34000: obj =   1.05880e+04  infeas =  5.004e-10 (2)
> | 34500: obj =   1.05880e+04  infeas =  2.476e-10 (2)
> | 34748: obj =   1.05880e+04  infeas =  4.083e-10 (2)
> + 34748: mip = not found yet >=   1.05880e+04(1; 0)
> + 34748: mip = not found yet >=   1.05880e+04(1; 0)
> TIME LIMIT EXCEEDED; SEARCH TERMINATED
> Time used:   120.8 secs
> Memory used: 160.7 Mb (168467811 bytes)
> Writing MIP solution to `./glpk_ex3/ex3_TAM_IP_glpk_step1.out'...
>
> Is it possible to print out the "OPTIMAL SOLUTION FOUND" in some way?
> The actual routing problem I am solving is a non-linear problem which
> I am modeling as a ILP to get a solution which is anyways not optimal
> for the problem but happens to be much better than a "random" solution.
>
> So, for the ILP, even if it is not an optimal solution, it is
> acceptable for my situation.
>
> Really appreciate your suggestions regarding this...
>
> Thanks & Regards,
> -Narendra

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Re: [Help-glpk] [Fwd: glpsol not converging]

[Xypron]

Hello Narendra,

glpsol has a command line parameter
--tmlim nnn   limit solution time to nnn seconds

Best regards

Xypron

On 26.07.2012 22:13, Andrew Makhorin wrote:
>  Forwarded Message 
> From: Narendra Devta-Prasanna 
> To: help-glpk@gnu.org
> Subject: glpsol not converging
> Date: Thu, 26 Jul 2012 12:23:43 -0700
>
> Hi,
>
> I am relatively new to using ILP solvers and do not understand all the
> underlying mathematics. I am using glpsol to solve a routing problem.
> For most instance of the problem, I get a solution within minutes. But
> in one case, when the size of the problem is bigger, it is not
> converging after running for more than 3 days and 10 million iterations.
> After about 12500th iteration, the objective function value does not
> improve but the tool does not ever stop.
>
> I have tried different options such as --first, --dfs, --pcost etc but
> nothing seems to help. I have also included "--mipgap 0.1" and also
> tried with other values but still does not help. Is there a way I can
> tell the tool to stop after a certain number of iterations and print the
> most optimal solution identified so far and make the results available
> through printf commands etc.
>
> I have looked all over the web for any further clues to solving this. I
> really appreciate it if the experts on this mailing list can help with
> how to address this issue.
>
> Thanks and Regards,
> -Narendra
>
>
>
>
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Re: [Help-glpk] [Fwd: Problem with GLPK when trying to find value functions]

[glpk xypron]

Hello Sergey,

a segmentation fault implies that you access memory for variables without 
having allocated the memory.

In the GLPK library index 0 is often not used. E.g. if you want to use function 
glp_set_mat_row to set 3 values you need to allocate memory for arrays with 4 
elements.

Please, have a close look at glpk-4.47/doc/glpk.pdf.

Best regards

Xypron

>  Forwarded Message 
> From: Sergey Kuznetsov 
> To: help-glpk@gnu.org
> Subject: Problem with GLPK when trying to find value functions
> Date: Wed, 25 Jul 2012 19:19:39 +
> 
> Hello,
> 
> 
> I'm using GLPK to find value functions, it's a family of linear programs
> with right-hand side as parameter. 
> For instance, I'm constructing 3D integer lattice and at each site
> (point) I need to find optimal solution using site coordinates as
> right-hand side (in this case it's 3D vector).
> I wrote a function that solves the linear program using GLPK. At first
> it crashed on the second call. I replaced glp_delete_prob() on
> gpl_erase_prob() and
> it worked well for [0;3]^3 lattice (and [0;3]^2 lattice). The problems
> began [0;4]^2 (2D) lattice. I have segmentation fault and it's unusual
> because in [0;3]^3 I'm solving more programs.
> OS : Linux Debian, i686;  Compiler: GCC  4.7.1
> Test instances: 3D: 4 columns, 3 rows; 2D: 3 columns, 2 rows;  all the
> entries (matrix, objective function coeff, right-hand side) are
> integers.
> Clearly, the problems begin when I'm setting span of the lattice to 4
> (5, 6, etc.).
> If anybody has any idea how to fix this, please help me.
> Thanks
> 
> 
> Sergey Kuznetsov   
> 
> 
> 
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Re: [Help-glpk] presolving

[glpk xypron]

Hello Daniele,

http://en.wikibooks.org/wiki/GLPK/Terminal_output#MIP_branch-and-cut_output
describes how to read the output to find out, when the first integer solution 
was found and which value it had.

If you have no need to prove optimality, you can use the following parameters 
for glpsol:

--tmlim nnn   limit solution time to nnn seconds
--mipgap tol  set relative mip gap tolerance to tol

Best regards

Xypron

 Original-Nachricht 
> Datum: Tue, 24 Jul 2012 11:08:23 +0200
> Betreff: Re: [Help-glpk] presolving

> the problem has no solution because of the constraints:
> *VincStraordinari1*and
> *VincStraordinari2*
> If i don't consider them, the problem has solution but takes days to find
> the
> solution.
> There is a procedure to shorten the search? Because I think that
> GLPSOLalmost immediately
> finds the solution but all this takes time to verify the optimality of
> this
> 
> (p.s. I use the command CUTS for resolve the problem)
> 
> Thanks
> 
> 2012/7/21 Daniele Micarelli 
> 
> > Hello
> > I have these two files that i attached
> >
> > because when i fix these two files with GLPSOL, it used too long (even
> > days) using the commands - math - cuts, and I wanted to know if there
> are
> > ways of presolving to speed the resolution
> >
> > thank you very mutch
> >
> > Best
> >
> > Daniele
> >

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Re: [Help-glpk] presolving

[Xypron]

Hello Daniele,

the model you appended is not solvable because:
- Manual work is required for the following activities
  set H := 3  4  5  6  7  8  25;
- The manual actvity is disallowed in time slots 1 to 720 (set TC).
- Activity 3 has to end latest in time slot 321 (param LST[3]).

Please, check your data file.

If you remove the following constraints the model is solvable
#subject to VincStraordinari1{i in H, t in TC}: x[i,t]=0 ; /* vincolo
sulle attività a configurazione manuale */
#subject to VincStraordinari2{i in H, t in TC: (t+ d[i]) in TC}:
x[i,t]=0 ; /* vincolo sulle attività a configurazione manuale */

$ glpsol -m File25attivita?MOD.mod  -d File25attivita?DAT.dat
+  2718: mip =   9.0e+03 >= tree is empty   0.0% (0; 91)
INTEGER OPTIMAL SOLUTION FOUND
Time used:   131.9 secs
Memory used: 880.4 Mb (923145628 bytes)

Best regards

Xypron

On 21.07.2012 15:35, Daniele Micarelli wrote:
> Hello
> I have these two files that i attached
>
> because when i fix these two files with GLPSOL, it used too long (even
> days) using the commands - math - cuts, and I wanted to know if there
> are ways of presolving to speed the resolution
>
> thank you very mutch
>
> Best
>
> Daniele
>
>
> ___
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Re: [Help-glpk] Single index for multidimensional sets

[glpk xypron]

Hello Mate,

a index symbol is always scalar and never a tuple. But you can use string 
concatenation for merging your indices:

set S1;
set S2;
set S3 := setof {s1 in S1, s2 in S2: s1!=s2} s1&","&s2;
set S4 := setof {s1 in S1, s2 in S2: s1=p[s3];

s.t. constraint2{s4 in S4}:
  x[s4] >= 2 * p[s4];

data;
set S1 := s11 s12;
set S2 := s21 s22 s23;
end;

Best regards

Xypron
 Original-Nachricht 
> Datum: Tue, 17 Jul 2012 15:30:07 +0200
> Von: Mate Hegyhati 
> An: help-glpk@gnu.org
> Betreff: [Help-glpk] Single index for multidimensional sets

> Dear All,
> 
> is it somehow possible to use a single index symbol for addressing an
> n-tuple? In one of my problems I have a 3 dimensional set, that is used
> as a basis for other sets, etc. I'm trying to do something like this:
> 
> set S1;
> set S2;
> set S3 := setof {s1 in S1, s2 in S2: s1!=s2} (s1,s2);
> 
> param p{s1 in S1, s2 in S2}, default 3;
> 
> var x{s3 in S3}; # this is, that should be (s1,s2) in S3
> 
> s.t. constraint1 {s3 in S3}: # similar here
>   x[s3]>=p[s3];
> 
> s.t. constraint2{s1 in S1, s2 in S2: s1   x[s1,s2] >= 2 * p[s1,s2];
> 
> It is not working, and according to the manual, an index should match
> the dimension of the set. Is it somehow possible to avoid writing
> (s1,s2) everywhere?
> 
> Thank You very much in advance, best regards,
> 
> Mate Hegyhati

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Re: [Help-glpk] glp_malloc: no memory available

[glpk xypron]

Hello David,

normally the matrices of LP problems are sparse.

Probably you will be using glp_set_mat_row, glp_set_mat_col, or glp_load_matrix 
in your code. Make sure that you only copy values that are not zero.

Make sure that you delete the vectors you are passing to said methods after 
usage.

ind = GLPK.new_intArray(3);
GLPK.intArray_setitem(ind, 1, 1);
GLPK.intArray_setitem(ind, 2, 2);
val = GLPK.new_doubleArray(3);
GLPK.doubleArray_setitem(val, 1, 1.);
GLPK.doubleArray_setitem(val, 2, -1.);
GLPK.glp_set_mat_row(lp, 1, 2, ind, val);
GLPK.delete_doubleArray(val);
GLPK.delete_intArray(ind);

Best regards

Xypron

 Original-Nachricht 
> Datum: Mon, 16 Jul 2012 13:44:19 -0400
> Betreff: [Help-glpk] glp_malloc: no memory available

> Hello,
> 
> I am building an LP using GLPK_4_47 in eclipse and am receiving the error:
> 
> glp_malloc: no memory available
> Error detected in file ..\src\glpenv05.c at line 70
> Exception in thread "main" org.gnu.glpk.GlpkException: function
> glp_add_rows failed
> at org.gnu.glpk.GLPKJNI.glp_add_rows(Native Method)
> at org.gnu.glpk.GLPK.glp_add_rows(GLPK.java:230)
> at
> cmif.LPWeighting.LPWeighting.developIMinusKConstraintsMax(LPWeighting.java:234)
> at cmif.LPWeighting.LPWeighting.singleOutputMaxLP(LPWeighting.java:56)
> at tests.MassSamplingLPTest.main(MassSamplingLPTest.java:30)
> 
> If anyone has any help at all, it would be much appreciated.  Thanks.
> 
> --David

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Re: [Help-glpk] problem with parameter

[glpk xypron]

Hello Daniele,

where is your problem in writing the data file?
A data file can have as many lines as you want.

set I:= {0..100};
set T:= {0..600};
param w{I,T};

data;
param w :=
  [  0,  0] 0.128312
  [  0,  1] 0.009597
...
  [  0,600] 0.029687
  [  1,  0] 0.553792
...
  [  1,600] 0.818264
...
  [100,600] 0.029687
...
  [100,600] 0.412226
end;

Just replace ... by the missing lines.

Best regards

Xypron

 Original-Nachricht 
> Datum: Mon, 16 Jul 2012 18:42:59 +0200
> Betreff: [Help-glpk] problem with parameter

> i have to write in file.DAT one parameter in two dimensions *w[i,t]*
> when *i* the index of the activity and *t* is the index of the time
> interval
> 
> My problem is that the time interval is 0..600 and i don't know how to
> write it on file.DAT because it is too large
> 
> I know its not about GLPK but i hope it's already happened to someone
> 
> thank you very much
> 
> best

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Re: [Help-glpk] set of commands

[glpk xypron]

Hello Daniele,

the options of glpsol are explained in appendix D of glpk-4.47\doc\glpk.pdf.

Or type
glpsol --help

To get an idea of what cuts are you may take a look at:
http://www.dei.unipd.it/~fisch/papers/slides/2010%20Toward%20a%20MIP-cut%20metascheme%20%5BFischetti%20CPAIOR%5D.ppt

Best regards

Xypron

 Original-Nachricht 
> Datum: Fri, 13 Jul 2012 00:49:49 +0200
> Betreff: [Help-glpk] set of commands

> what is the difference between the commands: math, cuts, no cuts and
> nointompt ???
> 
> thank you very much
> 
> best

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Re: [Help-glpk] [Fwd: GLPK NOT FUNCTIONING ON MY SYSTEM]

[glpk xypron]

Hello Imsmaila,

your message hat to be forwarded manually because you are not subscribed to the 
GLPK help list, see
https://lists.gnu.org/mailman/listinfo/help-glpk

If you want to compile GLPK yourself, see
http://en.wikibooks.org/w/index.php?title=GLPK/Obtaining_GLPK
http://en.wikibooks.org/wiki/GLPK/Windows

Otherwise download a precompiled version, see
http://en.wikibooks.org/wiki/GLPK/Windows_executables

Best regards

Xypron

>  Forwarded Message 
> Subject: GLPK NOT FUNCTIONING ON MY SYSTEM
> Date: Wed, 11 Jul 2012 11:28:09 -0700 (PDT)
> 
> Dear sir/madam, am a student of operations research from Nigeria.First i
> want to thank you for the free linear programing kit project.I download
> it on my system (windows 7 operating sys) plus the corresponding sig
> file but when i try to open it,a dialogue box pup up saying window
> cannot open this file.what should i do? Where can i get the tutorial?.
> Please advice. Ismail 
> 
> 
> 
> 
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Re: [Help-glpk] Retrieving Solution Values

[glpk xypron]

Hello David,

unfortunately your mail does not give sufficient information to analyze your 
problem.

Please, provide:
- version of GLPK
- version of the GLPK to Java binding used
- a reproducable example.

A .simplex() method existed in the GLPK 4.8 Java Interface published by Björn 
Frank, which is no longer maintained and cannot be used with current versions 
of GLPK, cf.
http://en.wikibooks.org/wiki/GLPK/Java

The current version of GLPK is 4.47.
The current version of GLPK for Java is 1.0.22 and is available at
http://sourceforge.net/projects/glpk-java/

Best regards

Xypron

 Original-Nachricht 
> Datum: Sun, 8 Jul 2012 21:16:10 -0400
> Betreff: [Help-glpk] Retrieving Solution Values

> Hi All,
> 
> I am a PhD Student that is using GLPK in Java and my problem is that when
> I
> create a problem, solve it, and attempt to retrieve the primal values of
> variables, it seems to be doing things out of order even though my code
> has
> the problem creation, .simplex() solution method, and then the retrieval
> code afterwards.  Even if I replace the retrieval code with just a
> System.out.println("SOMETHING") it still prints that before the console
> print of the actual solution of the problem.  Any help at all is much
> appreciated.
> 
> --
> David Myers

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Re: [Help-glpk] How did you rewrite the cplex API?

[glpk xypron]

Hello Christophe-Marie,

whether API definitions are copyrightable has been subject to legal disputes.

In a case between Google and Oracle in the US it was decided that API 
definitions are not copyrightable:
"So long as the specific code used to implement a method is different, anyone 
is free under the Copyright Act to write his or her own code to carry out 
exactly the same function or specification of any methods used in the Java API. 
It does not matter that the declaration or method header lines are identical. 
Under the rules of Java, they must be identical to declare a method specifying 
the same functionality — even when the implementation is different. When there 
is only one way to express an idea or function, then everyone is free to do so 
and
no one can monopolize that expression. And, while the Android method and class 
names could have been different from the names of their counterparts in Java 
and still have worked, copyright protection never extends to names or short 
phrases as a matter of law."
http://www.courthousenews.com/2012/06/01/Gcopyright.pdf

A likewise decision exists for the EU:
http://curia.europa.eu/juris/documents.jsf?num=C-406/10

Best regards

Xypron



 Original-Nachricht 
> Datum: Sun, 8 Jul 2012 13:13:14 +0200

> Betreff: [Help-glpk] How did you rewrite the cplex API?

> Hi,
> 
> Browsing the glpk sources, I found the following file:
> examples/cplex/cplex.h
> 
> I am the author of lazylpsolverlibs [1], a project aiming at
> generating proxy libraries for commercial lp solvers. My goal is to
> provide opensource libraries to link to for open source programs that
> use commercial lp solvers. These libraries transparently proxy calls
> to the closed-source ones whenever the solver can be found on the
> machine. My primary target is Osi [2], but I think other opensource
> implementations can benefit from such a work.
> 
> Right now, what bothers me the most is copyright issues. Implementing
> proxy functions is not a problem, but writing headers in a way I can
> redistribute them freely gives me headaches. As a consequence, I am
> interested in knowing about the way you wrote this file. Did you start
> from the actual cplex.h? Did you rewrite it from scratch?
> 
> Cheers,
> Christophe-Marie
> 
> [1]: https://code.google.com/p/lazylpsolverlibs/
> [2]: https://projects.coin-or.org/Osi
> 
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Re: [Help-glpk] Problem Has no Primal Feasible Solution

[glpk xypron]

Hello Daniele,

take a look at this constraint:

/* temporal precedence constraint */
subject to PrecTemp{i in A,j in A}: sum{t in T} tt[t]*x[j,t] >= sum{t in T} 
tt[t]*x[i,t] + d[i];

For i = j it requires non-positive durations 0 >= d[i].

Best regards

Xypron

 Original-Nachricht 
> Datum: Fri, 6 Jul 2012 12:25:58 +0200
> Von: Daniele Micarelli 
> An: help-glpk@gnu.org
> Betreff: [Help-glpk] Problem Has no Primal Feasible Solution

> Hi,
> i'm attaching the two file  .mod and .dat to let you know
> 
> When i run these files with glpsol,  i get these two messages at the end:
> 
> *Model has been successfully generated
> and
> PROBLEM HAS NO PRIMAL FEASIBLE SOLUTION
> 
> *in my opinion should exist one solution
> 
> it's possible?

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Re: [Help-glpk] Huge Parameter Sets

[glpk xypron]

Hello Andrew,

the GMPL language causes a huge memory overhead. Hence you should not use 
glpsol but the GLPK library, which you can call from C, C++, Java, Python, and 
some other programming languages.

Best regards

Xypron

 Original-Nachricht 
> Datum: Fri, 6 Jul 2012 17:04:40 -0300
> Betreff: [Help-glpk] Huge Parameter Sets

> Hello,
> 
> I'm trying to build a .mod model with data from ten 25,000,000 row .csv
> files (approx 500,00Mb each).
> 
> Even building a model with one of them gives an insufficient memory error.
> 
> Is there a better way to go about this than massive .csv files?
> 
> Does anyone have any experience with building models from such huge data
> sets?
> 
> cheers,
> Andrew
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Re: [Help-glpk] manipulating parameter indices

[glpk xypron]

Hello Kevin,

setABC will be calculated once only.

Best regards

Xypron

 Original-Nachricht 
> Datum: Wed, 04 Jul 2012 15:32:51 -0400
> Betreff: Re: [Help-glpk] manipulating parameter indices

> At 10:03am -0400 Wed, 04 Jul 2012, Andrew Makhorin wrote:
> > In the current mathprog implementation no query optimization is
> > performed, that is, all intermediate and resulting objects are
> > evaluated literally as specified by corresponding expressions. (This
> > is exactly the same problem that appears in the relational database
> > systems.) For example,
> >
> > param foo{i in I} := sum{j in J: (i,j) in E} x[i,j];
> >
> > will be evaluated as follows:
> >
> > for all i in I do
> > {  s := 0;
> >for all j in J do
> >{  if (i,j) in E then
> >  s := s + x[i,j]
> >}
> >foo[i] := s
> > }
> 
> Ah, I see.  So how about a compound situation like below?
> 
># i.e. a generated set.  Does this get created once and then used as
># a "first class" set?  Or does the "such that" operator get
># evaluated for every use if setABC?
> set setABC := {a in setA, b in setB, c in setC : a + b = c };
> 
> set setABCD := {(a, b, c) in setABC, d in setD : a + c = d };
> 
> s.t. C1 {(a, b, c) in setABC} :
>   VarX[a, b, c] <=  sum{(a, b, c, d) in setABCD} ParamX[a, b, c, d];
> 
> s.t. C2 {(a, b, c) in setABC} :
>   VarX[a, b, c] >= -sum{(a, b, c, d) in setABCD} ParamY[a, b, c, d];
> 
> So, when executing the s.t. line of C1, if setABC has not yet been used, 
> does it get "instantiated" before C1 gets to use it, or is the code 
> '(a, b, c) in setABC' effectively now an alias for:
> 
> {a in setA, b in setB, c in setC : a * c > 10}
> 
> such that it's use in the C2 constraint does not get the benefit of the 
> cached result?
> 
> In a similar vein, is there a more efficient method to sum over common 
> indices?  In other words, the fact that a, b, and c are already set in 
> the loop for '(a, b, c, d) in setABCD'?  As I understand the pseudo-code 
> above, those lines translate to something like
> 
> {
> s := 0
> for all (da, db, dc, d) in setABCD do {   # da = "dummy a"
>if a == da and b == db and c == dc then
>   s := s + ParamX[a, b, c, d]
> }
> }
> 
> If this is case, would it behoove to me create my own specific cache 
> subsets, like
> 
># return sets of (a,b,c) that return d in setABCD
> set D_ABC{(a, b, c) in setABC} := setof{(a,b,c,d) in setABCD} d;
> 
> And then use as:
> 
> s.t. C1 {(a, b, c) in setABC} :
>   VarX[a, b, c] <=  sum{d in setD_ABC[a, b, c]} ParamX[a, b, c, d];
> 
> Many thanks for your input, Andrew!
> 
> Kevin
> 
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Re: [Help-glpk] out of domain

[glpk xypron]

Hello Daniele,

set K;
data;
set K := 0..Deadline ;
end;

defines that K is a set containing one string with value "0..Deadline".

There is no operator ".." available in the data section.

Might it be that you wanted to write something like:

set SLA;
param Deadline{SLA};
set K{i in SLA} := {0..Deadline[i]};
solve;
display K;
data;
set SLA := A17 A18 A25;
param Deadline :=
  A17  32
  A18  40
  A25  44 ;
end;

Best regards

Xypron


 Original-Nachricht 
> Datum: Tue, 3 Jul 2012 23:15:39 +0200
> Von: Daniele Micarelli 
> An: help-glpk@gnu.org
> Betreff: [Help-glpk] out of domain

> Hi,
> i have this bond:  *subject to DLINE{i in SLA}: sum{t in K} x[i,t]=1 ; */*
> vincolo di Deadline sulle SLA */  in the file.mod
> 
> where the set K is defined as: *set K := 0..Deadline ; *in the file.dat
> *
> *Deadline is a parameter defined in the file.dat :
> *param Deadline :=
> 
> A17  32
> A18  40
> A25  44 ;*
> 
> When A17,A18 and A25 are activities and 32,40 and 44 are the values
> ​​of the
> corresponding deadline
> 
> But when i try i get this error: x[A17, "0..Deadline"] out of domain
> what it means?
> how can i fix it?
> 
> thank you very much

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Re: [Help-glpk] cannot convert 1..720 to floatin-point number

[glpk xypron]

Dear Daniele,

the data section does not allow the same syntax as the model section.

Please read chapter
5.2 Set data block
of glpk-4.47/doc/gmpl.pdf

You could write:
param tmax;
set T:= {1..tmax};
data;
param tmax := 720;
end;

Best regards

Xypron


 Original-Nachricht 
> Datum: Mon, 2 Jul 2012 22:50:48 +0200
> Von: Daniele Micarelli 
> An: help-glpk@gnu.org
> Betreff: [Help-glpk] cannot convert 1..720 to floatin-point number

> Hi
> in the file.MOD i declare the set T
> set T;
> I wrote in the file.dat
> set T: = 1 .. 720;
> 
> but when i try i get the error:
> 
> *cannot convert 1..720 to floatin-point number
> *
> What should I do?
> 
> If needed I can attach file.mod file.dat complete
> 
> thank you very much

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Re: [Help-glpk] post-processing without defined variables?

[glpk xypron]

Hello Kevin,

either you can use the GLPK library from another programming language (C, Java, 
...) or you can use scripting around glpsol, cf.
http://en.wikibooks.org/wiki/GLPK/Scripting_plus_MathProg

Best regards

Xypron

 Original-Nachricht 
> Datum: Sat, 30 Jun 2012 19:52:41 -0400
> Betreff: [Help-glpk] post-processing without defined variables?

> Hello GLPK List,
> 
> I see from the GLPK Wikibook that there's no ability to create reporting 
> variables (err, just learned that others call them "defined variables").
> 
> https://en.wikibooks.org/wiki/GLPK/GMPL_Workarounds#Mimicking_an_AMPL_defined_variable
> 
> I want to explore the last sentence in that section ("But you can use a 
> structural variable and a constraint instead to achieve the same effect 
> — the downside being that this formulation may render your problem 
> harder to solve").  The models that I'm working with are necessarily 
> large (roughly 1e5 [C] x 1e5 [R], give or take an order of magnitude 
> depending on the input), and I'd like to avoid adding any more variables 
> to the solver's matrix.
> 
> Given that I can't create constraints /after/ a solve statement (i.e. to 
> re-solve starting from the previous solution), does that mean that my 
> only option is a post-GMPL step with another tool (e.g. C, Perl, Python)?
> 
> Thanks,
> 
> Kevin
> 
> 
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Re: [Help-glpk] pick element from set?

[glpk xypron]

Hello Kevin,

there is no function that will return an element of a set (except for 
one-dimensional numeric sets).

You can create subsets.

e.g.

set X, dimen 2 := {(5, 7), (1, 10), (23, -3), ("y", "x"), ("a", "abc")};
set S := setof{(i,j) in X : forall{(k,l) in X} i <=k && j <= l} (i,j);

see
http://en.wikibooks.org/wiki/GLPK/GMPL_Workarounds#Sorted_output

Best regards

Xypron

 Original-Nachricht 
> Datum: Sun, 01 Jul 2012 03:11:00 -0400
> Betreff: [Help-glpk] pick element from set?

> Hello GLPK List,
> 
> Is there a method to pick an arbitrary single item from a set?  I don't 
> care which one, but I need to have a single element from a set such that 
> I can uniquely and consistently identify it.
> 
> There is no order to the set, but /if/ there were an ordering to this 
> set, I might reference this element as "nought".  Put differently, say I 
> have a set X:
> 
> set X, dimen 2 := {(5, 7), (1, 10), (23, -3), ("y", "x"), ("a", "abc")};
> 
> Is there functionality -- say a function called "pick()" -- to pick an 
> arbitrary element from that set?
> 
> Put another way, /if/ I could put that set into a list:
> 
> list(X) == [(5, 7), (1, 10), (23, -3), ("y", "x"), ("a", "abc")]
> 
> then I could get an arbitrary element, perhaps like 'get(list(X), 0)'.
> 
> Is there a method to grab a single element from the set?
> 
> I'll point out that I have an ad-hoc method of this for a 
> single-dimensional set (using a nested setof structure and a comparison 
> operator), but can't do it for any higher-dimensionality sets.
> 
> Thanks,
> 
> Kevin
> 
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Re: [Help-glpk] manipulating parameter indices

[glpk xypron]

Hello Kevin,

try the following:

set EFF, dimen 5;
set inputs := setof{(i,p,v,o,e) in EFF}i;
set process := setof{(i,p,v,o,e) in EFF}p;
set vintage := setof{(i,p,v,o,e) in EFF}v;
set outputs := setof{(i,p,v,o,e) in EFF}o;
set S := setof{(i,p,v,o,e) in EFF} (i,p,v,o);
param eff{(i,p,v,o) in S} := sum{(i,p,v,o,e) in EFF}e;
solve;
display eff;
data;
set EFF :=
# input processvintage output  efficieny
  coal  coal_pp2015electricity 0.4
  uranium   nuclear_pp 2015electricity 0.4
  sunlight  passive_solar  2020heat0.6;
end;

Best regards

Xypron
 Original-Nachricht 
> Datum: Fri, 29 Jun 2012 15:12:19 -0400
> Betreff: [Help-glpk] manipulating parameter indices

> Hello GLPK list,
> 
> Is there a method for collecting user-specified parameter indices into 
> an n-dimensional set?
> 
> I'm trying to reduce the amount of "knobs" I have to twiddle on a model 
> with which I'm working, and it dawned on my that I have a parameter 
> whose /indices/ contain valuable information that the rest of my model 
> could use.
> 
> For the sake of argument, this model has the notion of inputs, 
> processes, and outputs, where the processes convert inputs to outputs. 
> However, processes only operate on 1 or 2 inputs, and only create 1 or 2 
> outputs.  Thus, it would be highly beneficial to automatically create 
> sparse index sets, if for no other reason than helping to check my 
> typing ability.  Consider these 5 sets:
> 
> set periods :=  2015  2020  2025  2030 ;
> set vintage :=  2015  2020  2025  2030 ;
> 
> set inputs  :=  coal  oil  uranium  sunlight  gasoline  diesel
>  electricity ;
> 
> set outputs :=  electricity  gasoline  diesel  heat  miles ;
> 
> set processes :=
> coal_pp  diesel_pp  solar_pp   nuclear_pp  refinery
> passive_solar  electric_heat  gas_car  diesel_car;
> 
> I might tie these together in my model through an efficiency parameter:
> 
> param  eff{i in inputs, p in process, v in vintage, o in outputs} :=
>coal  coal_pp2015  electricity   0.4
>uranium   nuclear_pp 2015  electricity   0.4
>sunlight  passive_solar  2020  heat  0.6
> ;
> 
> While it makes sense for a coal power plant to take coal as input, and 
> produce electricity, it does not makes sense for a diesel_car to take 
> take heat and produce sunlight.  Consequently, that combination does not 
> exist in the eff parameter indices.
> 
> Rather than create an explicit 3-dimensional set that I must manually 
> populate, only to turn around and manually specify the same set for each 
> index in the eff parameter indices, is it possible to harvest the 
> information contained in the parameter indices?  I might use this to 
> automatically generate the set of valid indices over which, say, the 
> usable life of each process might be:
> 
> param  usable_life {(p,v) in valid_processes} default 30 :=
> coal_pp 2015   15
> coal_pp 2020   17   # GLPK would ostensibly provide an error
> # message because the eff parameter does
> # not have the  tuple in
> # the (p,v) subset of it's indices.
> ;
> 
> Does this functionality exist in GLPK?  I know at least one other 
> modeling system that provides for it, so I'm hoping that I've just 
> missed something in the gmpl.pdf documentation.
> 
> Thanks,
> 
> Kevin
> 
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Re: [Help-glpk] glpsol, arbitrary precision and large numbers

[glpk xypron]

Andrew already indicated the LP tolerances to you.
http://lists.gnu.org/archive/html/help-glpk/2012-06/msg00051.html

Best regards

Xypron

 Original-Nachricht 
> Datum: Fri, 29 Jun 2012 10:42:35 +0100
> Betreff: Re: [Help-glpk] glpsol, arbitrary precision and large numbers

> On Wed, Jun 27, 2012 at 01:03:35PM +0100, Edd Barrett wrote:
> > Which is false, so under this assignment the system in infeasible. The
> solver
> > should have either tried a different assignment of either variables, or
> if it
> > could not, then it should have reported the problem infeasible? Right?
> 
> Any thoughts on this? I am keen to figure out what went wrong here.
> 
> Cheers
> 
> -- 
> Best Regards
> Edd Barrett

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Re: [Help-glpk] help

[glpk xypron]

Hello Daniele,

sorry got it wrong.

param R;
param T;
set W;
param r{W};
param d{W};
set Q{i in W} := {1-d[i]..T-1};
var x{i in W, Q[i]}, >= 0;
maximize objective:
  sum{i in W, q in Q[i]} x[i,q];
s.t. constraint{t in {1..T}}:
  sum{i in W} sum{q in Q[i]} r[i] * x[i,q] <= R;
data;
set W := a b;
param R := 10;
param T := 5;
param d :=
  [a] 2
  [b] 3;
param r :=
  [a] .5
  [b] .7;
end;

Best regards

Xypron
 Original-Nachricht 
> Datum: Thu, 28 Jun 2012 06:22:13 +0200
> Betreff: Re: [Help-glpk] help

> Hello Daniele,
> 
> the following model contains a constraint of the type you refer to.
> Please, read glpk-4.47/doc/gmpl.pdf carefully. It is included in the
> source distribution of GLPK available at
> ftp://ftp.gnu.org/gnu/glpk/glpk-4.47.tar.gz
> 
> param R;
> param T;
> param t;
> set Q := { 1..T };
> set W;
> param r{W};
> param d{W};
> var x{W,Q}, >= 0, <=10;
> maximize objective:
>   sum{i in W, q in Q} x[i,q];
> s.t. constraint:
>   sum{i in W} sum{q in Q : q >= t-d[i] && q <= t-1} r[i] * x[i,q] <= R;
> data;
> set W := a b;
> param R := 10;
> param T := 5;
> param t := 6;
> param d :=
>   [a] 2
>   [b] 3;
> param r :=
>   [a] .5
>   [b] .7;
> end;
> 
> Best regards
> 
> Xypron
>  Original-Nachricht 
> > Datum: Wed, 27 Jun 2012 11:02:27 +0200
> > Betreff: Re: [Help-glpk] help
> 
> > Re: [Help-glpk] help
> > 
> > I have attached the image so it is clearer
> > W is a set of tasks
> > T is the set of the time allowed
> > r (i) is the parameter of the requested resource the activity i-th
> > d (i) is the duration of the i-th activity
> > R is the parameter that represents the total resource available in the
> > system
> > X (i, q) is the variable
> > 
> > Thanks
> > 
> > 
> > 2012/6/27 glpk xypron 
> > 
> > > Hello Daniele,
> > >
> > > from your description it is unclear what you mean by t.
> > >
> > > Is t the run parameter of the summation or is it a parameter
> controlling
> > > the boundaries of the summation? It cannot be both.
> > >
> > > Please, write down your equation completely including the definition
> of
> > > the sets and parameters. Either send it in tex or append an image
> file.
> > >
> > > Best regards
> > >
> > > Xypron
> > >
> > >  Original-Nachricht 
> > > > Datum: Tue, 26 Jun 2012 23:46:10 +0200
> > > > Betreff: Re: [Help-glpk] help
> > >
> > > > Re: [Help-glpk] help
> > > >
> > > > r (i) is a parameter and represents the resource request from the
> i-th
> > > > activities by the system.
> > > > The variable is x (i, t) where i is the index of the activities of
> the
> > > > whole W and t is the index of the time interval.
> > > > R is the total available resource is not exceeded while d (i) is the
> > > > duration of the i.th activity
> > > >
> > > > >
> > > > >
> > > > >
> > > > >> On Tue, 26 Jun 2012, Daniele Micarelli wrote:
> > > > >>
> > > > >>  I have to solve a linear programming problem with the language
> and
> > > I'm
> > > > >>> planning mathprog
> > > > >>> I have difficulty writing the following constraint: ΣΣ r (i) *
> x
> > (i,
> > > > t)
> > > > >>> <= R
> > > > >>> where the first summation is true for all belonging to the W and
> > the
> > > > >>> second
> > > > >>> summation has as its lower end t-d(i) and upper bound as t-1
> > > > >>>
> > > > >>
> > > > >> You've not made it clear what is a variable and what is not.
> > > > >> If r and x are both variables, you are done.
> > > > >> *Linear* programming does not involve products of variables.
> > > > >>
> > > > >> --
> > >
> > > --
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> > >
> 
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