On Wed, 14 Oct 2009, Alexander Schnell wrote:
> i have found out a formulation for your problem but the linear formulation is
> quite long:
>
> the nonlinear formulation is quite short:
> c = d*b*(b-a)+ e*a*(a-b).
>
> So now you can substitute the term d*b*(b-a) by the variable x and the term
>
Alex,Michael,Andrew,Larry-
Thanks a lot for all the help and the great discussion. I'll summarize the
different approaches in a separate email for future reference.
Regards
Kretch.
On Wed, Oct 14, 2009 at 1:45 AM, Alexander Schnell wrote:
> Hi there,
>
> i have found out a formulation for yo
Hi there,
i have found out a formulation for your problem but the linear formulation is
quite long:
the nonlinear formulation is quite short:
c = d*b*(b-a)+ e*a*(a-b).
So now you can substitute the term d*b*(b-a) by the variable x and the term
e*a*(a-b) by the variable y.
b*(b-a) is the produ
On Tue, 13 Oct 2009, Yaron Kretchmer wrote:
> Michael,
> I'm sorry, but I didn't understand your explanation below- This is due to my
> limited LP/MIP understanding- sigh..
You might want to look up convex hull and facet.
> But, looking at the examples on
> http://www.aimms.com/aimms/download/ma
> Now I #39;d like to be able to model conditional non-binary
> variables. Does anybody know how to formulate this in mathprog?
> --Begin Description ---
> *) a,b are binary
> *) c,d,e is continuous.
> *) I #39;d like c to be
> - 0 if a=b=0
> - d if a=0,b=1
> -
> Now I #39;d like to be able to model conditional non-binary
> variables. Does anybody know how to formulate this in mathprog?
> --Begin Description ---
> *) a,b are binary
> *) c,d,e is continuous.
> *) I #39;d like c to be
> - 0 if a=b=0
> - d if a=0,b=1
> -
On Mon, 12 Oct 2009, Yaron Kretchmer wrote:
> Thanks Michael
> Yes, the differences (and the variables themselves) are bounded. We can
> denote the the upper/lower limit for each variable/difference by the
> constants l(x) and u(x).
First, I made a mistake:
The sets have seven extreme points each
Michael,
I'm sorry, but I didn't understand your explanation below- This is due to my
limited LP/MIP understanding- sigh..
But, looking at the examples on
http://www.aimms.com/aimms/download/manuals/AIMMS3OM_IntegerProgrammingTricks.pdfand
doing some math led me to the following formulation:
Thanks Michael
Yes, the differences (and the variables themselves) are bounded. We can
denote the the upper/lower limit for each variable/difference by the
constants l(x) and u(x).
What would the formulation be in that case?
Regards
Yaron
On Mon, Oct 12, 2009 at 7:39 PM, Michael Hennebry <
henn
This might bounce from the mailing list.
NDSU has been mucking with my return address.
On Mon, 12 Oct 2009, Yaron Kretchmer wrote:
> Now I'd like to be able to model conditional non-binary variables. Does
> anybody know how to formulate this in mathprog?
>
> --Begin Description --
This might bounce from the list.
NDSU is mucking with my return address.
Kretchmer wrote:
> Thanks Larry. What I was looking for is for a way of forcing the "C"
> variable to equal values per the truth table.
>
> If "C" was binary I could achieve this by a series of inequalities without
> big M, a
arry - TX
> *Sent:* Monday, October 12, 2009 3:42 PM
> *To:* Yaron Kretchmer; help-glpk
> *Subject:* RE: [Help-glpk] More conditional variables fun
>
>
>
> Try thinking in terms of a Big M or large variable method. For instance…
>
>
>
> continuous variable expressio
f
D'Agostino, Larry - TX
Sent: Monday, October 12, 2009 3:42 PM
To: Yaron Kretchmer; help-glpk
Subject: RE: [Help-glpk] More conditional variables fun
Try thinking in terms of a Big M or large variable method. For instance...
continuous variable expression < (some large number) (binary var
k-bounces+larry.d'agostino
> =gmacrescap....@gnu.org] *On Behalf Of *Yaron Kretchmer
> *Sent:* Monday, October 12, 2009 3:24 PM
> *To:* help-glpk
> *Subject:* [Help-glpk] More conditional variables fun
>
>
>
> Hi There.
> Using feedback I got from the mailing list,
27;agostino=gmacrescap@gnu.org
[mailto:help-glpk-bounces+larry.d'agostino=gmacrescap@gnu.org] On Behalf Of
Yaron Kretchmer
Sent: Monday, October 12, 2009 3:24 PM
To: help-glpk
Subject: [Help-glpk] More conditional variables fun
Hi There.
Using feedback I got from the mailing lis
Hi There.
Using feedback I got from the mailing list, I was able to formulate binary
conditional variables.
Now I'd like to be able to model conditional non-binary variables. Does
anybody know how to formulate this in mathprog?
--Begin Description ---
*) a,b are binary
*)
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