Module Name:	pkgsrc
Committed By:	adam
Date:		Sun Nov 25 18:47:50 UTC 2007

Modified Files:
	pkgsrc/math/glpk: Makefile distinfo

Log Message:
Changes 4.24:
A tentative implementation of MIR (mixed integer rounding) cuts
was included in the MIP solver. To enable generating MIR cuts
the control parameter mir_cuts passed to the routine glp_intopt
should be set to GLP_ON. This feature is also available in the
stand-alone solver glpsol via command-line option '--mir'. For
more details please see the reference manual included in the
distribution.

The implementation is mainly based on the following two papers:

1. H. Marchand and L. A. Wolsey. Aggregation and mixed integer
   rounding to solve MIPs. CORE discussion paper 9839, CORE,
   Universite catholique de Louvain, June 1998.

2. G. Andreello, A. Caprara, and M. Fischetti. Embedding cuts
   in a Branch&Cut framework. Preliminary draft, October 2003.

MIR cuts can be generated on any level of the search tree that
makes the GLPK MIP solver to be a real branch-and-cut solver.

A bug was fixed in the routine lpx_write_cpxlp. If a variable
x has upper bound and no lower bound, it should appear in the
bounds section as "-inf <= x <= u", not as "x <= u". Thanks to
Enric Rodriguez <erodri@lsi.upc.edu> for the bug report.


To generate a diff of this commit:
cvs rdiff -r1.16 -r1.17 pkgsrc/math/glpk/Makefile
cvs rdiff -r1.13 -r1.14 pkgsrc/math/glpk/distinfo

Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.