Jonasz Staszek

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3. Indicator Constraint Definition for Bounds

Hi Phillip, you can model this via indicator constraints. Perhaps these two posts (here and here) will be helpful. Best regardsJonasz  

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• Jonasz Staszek
• October 13, 2022 08:56
• 1 vote

1. Community
2. Programming
3. LP Problem Formulation

I can't see any obvious red flags from afar. In the future, we will be better able to help you if you paste your code (and format it as such) in the post, rather than pasting a screenshot. To asses...

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• Jonasz Staszek
• October 13, 2022 07:25
• 1 vote

1. Community
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3. LP Problem Formulation

Dear Mohamad, I believe these resources (here and here) should be of help to you. Best regardsJonasz

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• Jonasz Staszek
• October 11, 2022 18:24
• 1 vote

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3. Create different models from "pool" of variables and constraints

Hi Andres, AFAIK both constraints and variables are specific to each model object in Gurobi. To get around this, you could for example declare your variables and constraints using only their indice...

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• Jonasz Staszek
• October 11, 2022 18:21
• Edited
• 1 vote

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3. Programming constrained clustering problem

Dear Micha, I recommend you familiarize yourself with these two (link, link) webinars about the basics of the use of Gurobi with Python. These should help you a great deal to arrive at the first im...

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• Jonasz Staszek
• October 04, 2022 09:09
• 1 vote

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3. Advanced Simplex Routines

Hi Ethan, as Jaromił pointed out in his contribution some time ago, the network simplex routine will be officially released with Gurobi 10.0. Perhaps someone from Gurobi team can comment further? B...

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• Jonasz Staszek
• September 23, 2022 07:55
• 1 vote

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3. How can I restrict a variable that can only take value in a list？

Dear Marika, dear Morris, as a workaround, one can try to use indicator variables and constraints to model the desired behaviour (have a look here for an example). This will most likely not scale w...

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• Jonasz Staszek
• September 22, 2022 13:39
• 0 votes

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3. Removing few variable from optimization model

I'm not sure I understood your question, but let me give it a try. Each variable has a VarName attribute. You could iterate over all the variables of the model, and check if "Journey2" is included ...

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• Jonasz Staszek
• July 21, 2022 10:35
• 1 vote

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3. Is there any function like count(X) in gurobi?

Hi Yikun, below comes my idea for tackling the problem you see. Perhaps someone from the Gurobi team can suggest a better approach? Generally, the idea would be to reformulate the model in such a w...

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• Jonasz Staszek
• July 21, 2022 09:41
• Edited
• 1 vote

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3. Removing few variable from optimization model

Hi Tanmoy, I am afraid you cannot delete variables when the optimization is running. Judging from the context of your post I assume you would like to remove variables after one optimization call ha...

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• Jonasz Staszek
• July 18, 2022 15:43
• Edited
• 1 vote