> Attached is the compressed file. > Thank you.
I guess you build your model by using glpk api routines. Please check your code, namely, all calls to glp_set_col_bnds. Looks like for some columns you specify the type GLP_DB and set lower and/or upper bounds to, resp., -DBL_MAX and +DBL_MAX; probably these "infinite" bounds come from earlier calls to glp_get_col_lb/ub. Such bounds are meaningless and should not be specified; unfortunately, glp_set_col_bnds doesn't check this error, which leads to the bug in the lp presolver. To avoid this error you need to check bounds before any call to glp_set_col_bnds and specify the column type appropriately, e.g. if (lb < -1e20 && ub > +1e20) type = GLP_FR; else if (ub > +1e20) type = GLP_LO; else if (lb < -1e20) type = GLP_UP; else if (fabs(lb - ub) < 1e-12) type = GLP_DB; else type = GLP_FX; glp_set_col_bnds(P, j, type, lb, ub); If, however, you obtain column bounds with glp_get_col_lb/ub, you may obtain corresponding column type with glp_get_col_type. Hope this helps. Please note that this error doesn't appear in 4.50 due to a happy chance only. Andrew Makhorin _______________________________________________ Bug-glpk mailing list [email protected] https://lists.gnu.org/mailman/listinfo/bug-glpk
