[Help-glpk] numerical instability

[Andrew Walbran]

Hi
I am working on building an LP model of an electricity market. I had a model 
that ran in about 20 seconds. After changing some of the input data, I ran it 
again, and this time GLPK kept giving the message:
'spx_simplex: numerical instability (primal simplex, phase II)'
and took much longer to run.

What does this message mean, and is there anything I can do about it to make 
my model run faster?

I am using GLPK 4.8. A copy of some of the output from GLPK is attached.

-- 
Andrew Walbran
website: http://user.interface.org.nz/~andrew/
blog: http://qwandor.wordpress.com/

GLPK_output.txt
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pgp_sWhqBDvNv.pgp
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