Originally posted by: SystemAdmin

[bistra said:]

Hi,
I have been fighting with this and cannot understand why it is happening.
I have an array of IloNumExpr's powExpr[][] that are highly nonlinear (constructing using IloPower etc)
then i create my obj function as a sum of these expressions.

Adding a bounding constraint to the obj works.
But when i try ot add a bounding constraint to the powExpr i get the exception.

Please help.


IloNumExpr obj(env);
for(i = 0; i < numloc; i++){<br /> for(j = 1; j <= numAngles; j++){<br /> obj += powExpr[j][i];

}
}

model.add(IloMaximize(env, obj));
model.add(0 <= obj); // works<br /> for(i = 0; i < numloc; i++){<br /> for(j = 1; j <= numAngles; j++){<br /> model.add(0 <= powExpr[j][i]); // bombs!!!<br /> }
}
#CPOptimizer
#DecisionOptimization

Originally posted by: SystemAdmin

[leon said:]

Hi Bistra,

I can't understand
[tt]obj += powExpr[j][/tt]
or
[tt]0 <= powExpr[j][/tt]<br />
Is powExpr a IloNumExpr[][size=10pt][b][][/b][/size] actually ?
#CPOptimizer
#DecisionOptimization

Originally posted by: SystemAdmin

[bistra said:]

The formatting removed the second index but yes i index powExpr [j] [ i ] in both the creating of the objective and in the constraint 0 <= powExpr [j] [ i ].<br />Adding the constraints  0 <= powExpr [j] [ i ] causes the exception. While commenting them out works fine.<br />
I don't understand why since the objective has these same expressions as sub expressions.
#CPOptimizer
#DecisionOptimization

Originally posted by: SystemAdmin

[leon said:]

The italic should have made me thinking ! :)
It looks like a bug but I tried something similar with my optimizer 2.3 (do you use this or solver ?), and I couldn't reproduce.
I'd rather try with your crashing powExpr
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