Re: [Help-glpk] Demande Urgents

[Andrew Makhorin]

> CheminOptique.mod:26: integrand following max{...} has invalid type
>  Context: ...; var lambdaM = max { i in I , j in I } lambdaIJ [ i , j
> ] ;
>  Model processing error
> 
>  I wanted to have the maximun of lamdba[i,j]

You want too much :) All constraints must be linear. You can try
reformulating your instance as follows:

var lambdaM;

s.t. foo{i in I, j in J}: lambdaM >= lambdaIJ[i,j];