Sabrin Rashwan

Thank you Jaromil for your prompt response. I used the if - statement incorrectly.  Now, I have applied your recommendations. and the model returns to work again. However, I faced another relevant ...

I have applied some Arc Elimination rules in the hope to get the model solved faster, but unfortunately, it gets slower. I compared the basic model and the model with arc elimination for a gap of 4...

Thanks a lot, Jaromił, I need i!=j because I iterate over i which are not in Cr but it will be in N\Cr and j is in N. As you may be noticed from my newer posts I am working more on getting ride of ...

I caught my mistake, infeasible-path1 should be infeasible_path1 Thanks a lot.

Hi Sonja, the infeasibility was due unreasonable quantity of a particular parameter (input data). This is how I thought to catch the error: after employing  m.computeIIS() and m.write("irreducible....

Thanks a lot, Jaromił Najman.  the Model.update()  worked well and my model composes of 2986 variables and 1686 constraints.    I am going to figure out how to use if-statement -as per your recomme...

Sonja, thanks a lot for your prompt reply. I have printed out the fr, constraint 6 and constraint 7. The output seems acceptable and the constraints correctly captured the required nodes. However, ...

@Jaromił Najman thanks a lot for your reply. With regard to set C , it is my mistake, it is actually as follow  C = set(range(10,22)) Returning back to the constraint in the image I have posted in ...

With regard to the yr[i,j] I have corrected to yr[r,i,j]

Thanks a lot I was searching for something like that.