[Help-glpk] Re: Help-glpk Digest, Vol 90, Issue 1

[Greg Gruber]

Hello,
I have a column-generation problem I'm trying to switch over from AMPL/CPLEX to GLPK, and it would be useful to be able to display the dual values in MathProg.  I know that suffixes are not supported in the official release, but I saw the following:

An unofficial patched version of a last year GLPK release can be
checked out with subversion

svn co http://glpk.dyndns.org/svn/glpk/branches/glpk-4.38-dot/

It supports the following suffixes in the post solution phase:

variables
lb - lower bound
ub - upper bound
val - value
dual - dual value
basic - 1 if variable is basic

constraints
lb - lower bound
ub - upper bound
dual - dual value
value - value

I downloaded this version using "vn co http://glpk.dyndns.org/svn/glpk/branches/glpk-4.38-dot/"  then compiled it (configure, make, make install).  The compile appears successful, and when I check the date/timestamp on my glpsol, it shows the current date/time.  When I try to use the ".dual" functionality as follows:

"display summation_constraint.dual;"

I get an error message:

"Reading model section from test_cur1_2.mod...
test_cur1_2.mod:67: invalid reference to constraint summation_constraint
Context: ...f MaxCHarn >> '...' ; solve ; display summation_constraint .
GLPK: model processing error"

Did I download the correct version?

Thanks,
Greg