Hello Terry, the MIP presolver calls scaling. If you disable the presolver no scaling is done. The MIP presolver is disabled by default.
glp_iocp iocp; glp_init_iocp(iocp); // iocp.presolve = GLP_OFF; glp_intopt(lp, iocp); cf. doc/glpk.pdf of the source distribution available at http://ftp.gnu.org/gnu/glpk/glpk-4.57.tar.gz Best regards Heinrich Schuchardt On 18.11.2015 05:36, Terry wrote: > I'm solving binary MIPs using these basic steps: > > mip = glp_create_prob(); > glp_read_lp(mip, NULL, filename); > parm.presolve = GLP_ON; > glp_intopt(mip, &parm); > status = glp_mip_status(mip); > > For all my MIPs, GLPK always says: > > Problem data seem to be well scaled > > Apparently it tries to scale it, and figures out it's unnecessary. I'm > solving many similar MIPs and would like it to skip this scaling step. > > I tried this before calling glp_intopt(): > > glp_scale_prob(mip, GLP_SF_SKIP); > > But, it still tells me it's well scaled. How can I skip it? > > Thanks, > Terry > > > _______________________________________________ > Help-glpk mailing list > [email protected] > https://lists.gnu.org/mailman/listinfo/help-glpk > _______________________________________________ Help-glpk mailing list [email protected] https://lists.gnu.org/mailman/listinfo/help-glpk
