Re: [Help-glpk] "multiplication of linear forms not allowed"

[Michael Hennebry]

On Sun, 21 Oct 2012, Meketon, Marc wrote:

> Xypron used "M" as a large constant (e.g., 9999).  Not as a binary variable.
>
>
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> param M := 9999;
>
> var B{J,K} >= 0;
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>
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> s.t. a{j in J}: -M*sum{k in  K}B[j,k] <= A[j] <= M*sum{k in K}B[j,k];

Simply picking a large value for one's big M is a bad idea.
One should try to at least approximate the smallest valid value.
M appears twice.
Probably they should be two different big Ms.

--
Michael   address@hidden
"On Monday, I'm gonna have to tell my kindergarten class,
whom I teach not to run with scissors,
that my fiance ran me through with a broadsword."  --  Lily