Iason Liagkas

Hello guys on a previous post I have found : https://support.gurobi.com/hc/en-us/community/posts/7197240325905-How-to-update-value-of-parameter-during-model-iteration-?input_string=model%20paramete...

Hello guys, in my lp file for the model description I am getting 0 as coefficient for a variable that should have coefficient=1. bellow is the output: Is there anything wrong with this?  \ Model SP...

Hello guys, do you know how does Gurobi handle the multiplication of two continuous variables under the hood?  I was searching how to linearize this calculation and I came across McCormick envelope...

Hello guys, I am running a code and every time I run it I get a different result in terms of time to get the solution and also in terms of optimality gap. The objective function has a different res...

Hello guys, I am modeling a problem relative to traffic equilibrium, and when I add more than a certain number of traffic origin-destination pairs it becomes infeasible. Does this mean that I am re...

Hello guys, I have been running a code that solves a problem but I do not know if the problem is feasible or not, so my questions are 1) if the log file has been running for 24 hours and I have not...

Hello guys, in a problem I run I get results. The algorithm used is dual simplex. Some repetitions produce infeasibility in the obj function but the final solution has a gap of 0%. This is the resu...

Hello guys, I used the code to write my model model.write('my_iis.ilp') In the file the objective function formula seems to be distorted:  The code that defines the objective function is: #objecti...

Hello people, how can we use the IIS variable bounds to determine infeasibility (if we can)? Should they be the same as what we set in our code in order not to cause any problems?Kind regardsIason

Hello guys, I am getting this message: Do you have anything to suggest? Is there any comment about my number of variables or constraints? Do you think my program is too big to be feasible? I just d...