[Help-glpk] spx_simplex: numerical instability (primal simplex, phase I) and infinite looping in glpk on large model

[rockwell]

glpk-help,

I am attaching 3 versions of the same model that differe in their 
limits on two rows.  KnockoutRow and KnockoutRow_up

All versions of the model display the error:
   spx_simplex: numerical instability (primal simplex, phase I)

However the version ec_kn10_kca_mps.txt loops infinitely

Also all column ending in _kcol are intended to be integer (actualy 
binary as their lower limit = 0 and upper limit = 1)).

I am attaching the output as well.

I have tried scaling my objective function (which has a coeffecent of 
1) by small numbers and scalling my limits as well but neither approach 
has helped remove the instabilities.

Graham Rockwell

ec_kn0_kc0_mps.txt created error1.txt
ec_kn10_kca_mps.txt created error2.txt


(I removed attachments, since they are very large. - Andrew Makhorin.)