Re: [Help-glpk] Slow performance on "Select minimum" task

[Michael Hennebry]

On Tue, 5 Jun 2018, Jan van Rijn wrote:

> I need to add two things:
> - It is my conjecture that there should be an additional constraint, i.e.,
> y[r,c] > 0 (Otherwise non-selected rows could participate towards a lower
> score)

Correct,

> - M[r,c] should contain positive values (which guarantees that y[r,c] == 1
> iff x[r] - SUM x[s] == 1)

I'm pretty sure that is not necessary.
the y's depend only on the x's and the order of the M values.
In any case, I think the zeros in your original problem
will not be much of an issue.
Consistent tie-breaking is important.

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