Re: [Help-glpk] Accessing shadow prices in stand alone LP/Solver

[xypron]

Hello Wafa,

unfortunately the current release does not support accessing dual values in
glpsol in the post processing phase.

I have suggested to patch GLPK to allow this.

You can download the patched source using subversion:
svn co svn://glpk.dyndns.org/svn/glpk/glpk/branches/glpk-4.35-dot/

For variables you can access lower bound (lb), upper bound (ub), dual value
(dual), value (val) of a variable x[3] like this:
x[3].dual
x[3].lb
x[3].ub
x[3].val

For constraints you can access lower bound (lb), upper bound (ub), dual
value (dual) of a constraint C[3] like this:
c[3].dual
c[3].lb
c[3].ub

Best regards

Xypron



Wafa.Rezig wrote:
> 
> 
> Hello,
> 
> I am using "result" command
> to access the decision variables in GLPK, but dont know how to access the
> shadow prices (marginal price)?
> Is there any documentation about all
> commands.
> Thanks 
> 
> Wafa Rezig
> OR Analyst
> AISystems, Belgium
> Phone: +32-2-558-88-23
> Mobile: +32-478-54-39-57
> 
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> 
> Hello,
> 
> I am using "result" command
> to access the decision variables in GLPK, but dont know how to access the
> shadow prices (marginal price)?
> Is there any documentation about all
> commands.
> Thanks 
> 
> Wafa Rezig 
> OR Analyst 
> AISystems, Belgium 
> Phone: +32-2-558-88-23 
> Mobile: +32-478-54-39-57 
> 
> Legal disclaimer 
> 
> This electronic message contains information that is confidential. The
> information is intended to be for  the use of the addressee only.
> If you are not the addressee we appreciate your notification in this
> respect
> and please note that any disclosure, copy, distribution or use of the
> contents
> of this message is prohibited and may be unlawful. We have taken every
> reasonable precaution to ensure that any kind of attachment to this e-mail
> has been swept for viruses. However, we cannot accept liability for any
> damage sustained as a result of software viruses and would advise that
> you carry out  your own virus checks before opening any attachment.
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