Re: [Help-glpk] invalid scale factor

[Andrew Makhorin]

>I have a quite big MIP problem with about 900 integer variables.
>Trying to optimize with glpk I get the following message:
>
>??? *** SEVERE CRITICAL ERROR *** from GLPK 
>lpx_set_rii: i = 5; rii = 0; invalid scale factor
>
>As I am not very familiar with MIP algorithms, can somebody explain
> what exactly is going wrong here?

Looks like there is a bug in some glpk mex interface routine (the
first error message comes from glpk mex, not from glpk). The error
appears because some glpk mex routine tries to set element R[5,5] of
the diagonal scaling matrix (used internally to scale rows) to zero,
however, all scale factors must be positive numbers.

Andrew Makhorin