help-glpk
[Top][All Lists]
Advanced

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [Help-glpk] glpk fails with error: unable to factorize basis matrix


From: Erwin Kalvelagen
Subject: Re: [Help-glpk] glpk fails with error: unable to factorize basis matrix (
Date: Tue, 21 Apr 2015 12:16:30 -0400

Probably a scaling issue. These numbers should scare the heck out of you:

Scaling...

 A: min|aij| =  1.000e+00  max|aij| =  2.306e+18  ratio =  2.306e+18

GM: min|aij| =  1.213e-04  max|aij| =  8.246e+03  ratio =  6.800e+07

EQ: min|aij| =  1.480e-08  max|aij| =  1.000e+00  ratio =  6.755e+07

2N: min|aij| =  1.490e-08  max|aij| =  1.500e+00  ratio =  1.007e+08



----------------------------------------------------------------
Erwin Kalvelagen
Amsterdam Optimization Modeling Group
address@hidden
http://amsterdamoptimization.com
----------------------------------------------------------------

On Tue, Apr 21, 2015 at 6:32 AM, Uday Reddy <address@hidden> wrote:
With glpk 4.52 and with the attached input, I get the following failure/error:

------------------------------------------------------------------------------
$ glpsol --lp mi.cplex

Warning: numerical instability (primal simplex, phase I)
   2979: obj =   1.092652474e+04  infeas =  5.265e+09 (0)
Warning: numerical instability (primal simplex, phase I)
   2996: obj =   1.092637382e+04  infeas =  5.260e+09 (0)
   3000: obj =   1.092644011e+04  infeas =  5.235e+09 (0)
Warning: numerical instability (primal simplex, phase I)
   3051: obj =   1.077725595e+04  infeas =  5.201e+09 (0)
Warning: numerical instability (primal simplex, phase I)
   3059: obj =   1.074805814e+04  infeas =  5.185e+09 (0)
Warning: numerical instability (primal simplex, phase I)
   3122: obj =   1.998434476e+03  infeas =  3.955e+05 (0)
Warning: numerical instability (primal simplex, phase I)
   3159: obj =   1.998431624e+03  infeas =  3.944e+05 (0)
Error: unable to factorize the basis matrix (1)
Sorry, basis recovery procedure not implemented yet
glp_intopt: cannot solve LP relaxation
Time used:   1.7 secs
Memory used: 10.8 Mb (11322915 bytes)
--------------------------------------------------------------

Any insights/workarounds will be appreciated.

_______________________________________________
Help-glpk mailing list
address@hidden
https://lists.gnu.org/mailman/listinfo/help-glpk



reply via email to

[Prev in Thread] Current Thread [Next in Thread]