Hello Reg (& others), Thanks a lot for your email.
As a fast step, I want to solve a mixed integer linear program like follows min c'x s.t. Ax <= b, lb <= x <= ub Some variables of x are binary ones. I have generated A, b, c, lb, ub in Matlab and stored them in .mat format. I have to convert them to GMPL readable format so that I can solve this code using GLPK. I have attached a sample of those files with my email. I will really appreciate if you could tell me how I can convert them using AWK. Please let me know if you want me to send a .mat file with smaller size. Your help will be very appreciated. Thanks, Nazmul On Fri, Dec 27, 2013 at 3:30 PM, Reginald Beardsley <[email protected]>wrote: > Nazmul, > > I suggest you consider using awk to generate data files in GMPL format > from ASCII text (.txt) files if you have very many instances to solve. You > put the problem formulation in one file and the data for each instance in > another file and execute "gplsol -m model.dat -d data.dat". I've found > this works very well solving large numbers of problem instances. In > particular, it makes changing the model very simple. I can't find out > anything about the Guesk editor so I can't comment on setting up GMPL > notation data files using that. > > I tried using the CSV import facility in GMPL, but found it not very > convenient because of restrictions on the CSV format glpk accepts. > > There is a MATLAB binding for GLPK, but I don't know how usable it is. > The MATLAB clone, Octave, also has a built-in binding to GLPK. > > http://en.wikibooks.org/wiki/GLPK/Matlab > > http://en.wikibooks.org/wiki/GLPK/Octave > > http://en.wikibooks.org/wiki/GLPK/Scripting_plus_MathProg > > There is a Gnu implementation of awk, gawk, which is standard on Linux > systems. It's also available on Windows. > > http://gnuwin32.sourceforge.net/packages/gawk.htm > > If you need help with writing an awk script to convert the MATLAB .txt > files to GMPL notation send me a small example of the MATLAB .txt file and > I'll add an example to the GLPK wiki. > > You'll need to figure out how to write a basic GMPL problem first. A good > place to look is in the examples directory at cf12a.mod which implements an > L1 line fit. I solve physics inverse problems by basis pursuit using GMPL > notation so I can probably offer some help. I do problems with 30,000 > columns by 50-300 rows. The resulting files are huge, so you want to get > everything working using a small example before doing something that large. > I did some little 10x10 problems to figure out how to set it up. > > Reg > > > > > -------------------------------------------- > On Thu, 12/26/13, Nazmul Islam <[email protected]> wrote: > > Subject: [Help-glpk] Import data from Matlab variables to GLPK/GMPL > To: [email protected] > Date: Thursday, December 26, 2013, 8:49 PM > > Hello, > I want to write my GLPK code through the Guesk > editor and I am very new to the GNU Math Programming > Language. > I want to import some data from Matlab to my GLPK > code. I want to run the code with these imported data. The > data is currently in some variables of Matlab and I can > store them in some .mat files. Do I need to save all these > Matlab variables in a single .dat file (or .txt file?) and > then import to GNU Math Prog language? > > Is there any example that I can > follow? > Thanks, > Nazmul > > > -----Inline Attachment Follows----- > > _______________________________________________ > Help-glpk mailing list > [email protected] > https://lists.gnu.org/mailman/listinfo/help-glpk > > > >
A.mat
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b.mat
Description: Binary data
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