# Jaromił Najman

Gurobi Staff
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## Activity overview

Latest activity by Jaromił Najman
• Jaromił Najman commented,

The index changes in your products list only affect the constant lists $$\texttt{a,l}$$. They don't affect the optimization variables $$\texttt{a1,a2,l1,l2,S}$$. Thus you made a few too many change...

• Jaromił Najman commented,

Hi Margi, Why did you put lb=-GRB.INFINITY here? The default lower bound for variables in Gurobi is $$0$$. But the value of EnergyResource - EPV might be negative. Thus, I set the lower bound of ...

• Jaromił Najman commented,

$$\texttt{S}$$ is a tupledict of optimization variables. Thus you have to access it as such via $$\texttt{S[p,t]}$$. Moreover, your constant lists $$\texttt{a,l}$$ are indexed over $$[0,1]\times [0... • Jaromił Najman commented, As the error states, there is no entry \(\texttt{S1[0,0]}$$. This is because now your products list starts with a 1. Thus, you have to adjust your product indices to also start with 1 when explicit...

• Jaromił Najman commented,

You give your variables the same name as indicated by the warning l2=m.addVars(products,weeks,obj=k,name='l2')l3=m.addVars(products,weeks,obj=k,name='l2') # should be 'l3'

• Jaromił Najman commented,

To initialize your variables, I think you should better use the addVars method instead of the addMVar method. Using optimization variables as indices for other entries is not easy and is discussed ...

• Jaromił Najman commented,

The issue is that you are adding variables S1[0,0],S1[1,0],S2[0,0],S2[1,0] to the objective function but later you don't use them, because you overwrite the dictionary entries by S1[0,0]=1S1[1,0]=2...

• Jaromił Najman commented,

Hi Margi, Now I am unsure why aux_constr_174_42 is repeating twice? How are $$\texttt{reslist2}$$ and $$\texttt{time1}$$ defined? Do you have duplicate entries in $$\texttt{reslist2}$$? This migh...

• Jaromił Najman commented,

My Model is infeasble In this case, please refer to How do I determine why my model is infeasible? There are two things which pop up. In your comment you want to define weeks as #weeks = [0,1,2,3...

• Jaromił Najman commented,

I will send you the model to understand the default it will better You don't have to send your model. You already posted the code snippet producing it which most likely has indexing issues. You s...