[Bug-glpk] debug reporting from glp_simplex (cosmetic issue)

[Robbie Morrison]

Hello bug list

This is essentially a cosmetic issue.  Note the
following output and, in particular, the redundant
'glp_simplex' reportage:

  Constructing initial basis...
  Size of triangular part = 26
        0: obj =   1.866666667e-11  infeas =  1.150e+08 (1)
        1: obj =   1.866666667e-11  infeas =  1.150e+08 (1)
  PROBLEM HAS NO FEASIBLE SOLUTION
  glp_simplex: unable to recover undefined or non-optimal solution
  GLPK Integer Optimizer, v4.45
  54 rows, 38 columns, 97 non-zeros
  1 integer variable,  which is binary

Here is a patch:

--- src/glpapi06.c.orig 2011-05-12 15:59:47.082202533 +0200
+++ src/glpapi06.c      2011-05-12 16:00:04.342703792 +0200
@@ -330,7 +330,7 @@
       /* only optimal solution can be postprocessed */
       if (!(ret == 0 && lp->pbs_stat == GLP_FEAS && lp->dbs_stat ==
             GLP_FEAS))
-      {  if (parm->msg_lev >= GLP_MSG_ERR)
+      {  if (parm->msg_lev >= GLP_MSG_DBG)
             xprintf("glp_simplex: unable to recover undefined or non-op"
                "timal solution\n");
          if (ret == 0)

---

In addition, it could be useful to consider a debug
reporting option for GLPSOL:

   --debug n         enable debug reporting (0 = off 3 = all)

all the best, Robbie
---
Robbie Morrison
PhD student -- policy-oriented energy system simulation
Technical University of Berlin (TU-Berlin), Germany
University email (redirected) : address@hidden
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