Adding conditional constraint based on index value
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The first dimension of your variables \(x_W\) and \(x_{FM}\) depends on \(\texttt{J1,J2}\), respectively. Thus, if you set \(\texttt{J1,J2}\) equal to \(0\), the tupledicts \(x_W\) and \(x_{FM}\) will be empty.
Is it correct that the terms \(\texttt{NFRM,NW,J1,J2}\) all are constant values determined before solving and constructing the model?
Could you elaborate a bit more on what actually you are trying to achieve with your code snippet? A minimal working example would also help.
Best regards,
Jaromił0 -
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I assume that NFM and NW are integer values \(\geq0\), correct? If yes, then you could add a constraint
\[\begin{align*}
x_W &\leq NW\\
x_{FM} &\leq NFM
\end{align*}\]This way, you force variables \(x_W, x_{FM}\) to \(0\) when the corresponding constant input is \(0\). You have to introduce this constraint for every variable depending on NW, NFM.
Best regards,
Jaromił0 -
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Thank you so much for your guidance. That is right. NFM and NW are integer values ≥0.
When for example NW=0, since J1 is null I receive error for the following constraint:
x-W[j1,l1]<=x-W[j-1,l1]
Is it correct to change it to the following?
If NW!=0:
x-W[j1,l1]<=x-W[j-1,l1]
Regards,
Bahar
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I don't know the structure of your code, but in general adding the \(\texttt{if NW!=0:}\) clause should work.
Best regards,
Jaromił0 -
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