0
$\begingroup$

I have got error with large-scale Problems that needs a solution by LinearProgramming, I am working on TSP Problem and I write the Linear Formulation for this Problem (Note: I know that there is a function in Mathematica "FindShortestTour" can give me the solution of this problem, but I need to solve the linear formula by myself), I write a code that can generate automatically the formula and give it to Function like NMinimize, I have no problem when the number of variables and constraints are small, it works very nice and there are no errors, The error appears when the size of problem is large so it gives me this error

"kernel is not responding to a dynamic evaluation"

for example when the number of cities in TSP is 50 we have 2500+50 variables and nearly 2500 constraint, I try to use NMinimize but it gives the error above then I try to use LinearProgramming Function and it also gives the same error I read in documentation that method simplex is not useful for large-scale problem and we must use InteriorPoint, I try to use it, but Mathematica gives error that it is unuseful when we have constraint that variable must have integer value (that is my case ), I try to use FindMinimum (although it gives local optimum not global which I want) and it also gives the same error, why this appears, I deal with these functions in other problems and sometimes it takes too long time (like 10 hours or days) to give solution but it last gives result and this is nice why here it stops and cannot give any solution what is the method to solve Linear large-scale problems in Mathematica please help me

Improve this question
$\endgroup$
7
  • 3
    $\begingroup$ The error quoted above is annoying but not directly the issue. It arises typically when there is dynamic content on the screen that gets triggered to update its display (e.g. from scrolling), while the kernel is locked in a computation and cannot be interrupted to handle the display update. Often this is because the kernel computation is in library code for which no interruption mechanism has been put into place. In this case it would most likely be whatever library code is being used to handle integer linear programming (ILP) problems. As for the slowness, well, ILP is hard. $\endgroup$
    – Daniel Lichtblau
    Jun 7, 2022 at 14:40
  • $\begingroup$ thank you, so what is the solution for this type of problems or to avoid this error $\endgroup$
    – user81348
    Jun 9, 2022 at 13:39
  • $\begingroup$ For speed issues, one very general possibility is to use different algorithms. For the "kernel is not responding..." issue, it depends on the exact cause. Some of the issues are version dependent and fixed in the most recent one (13.0.1). Do you have details of what was happening when you encountered the issue (in particular, what was going on in the user interface)? Also what version of Mathematica are you using? $\endgroup$
    – Daniel Lichtblau
    Jun 9, 2022 at 15:57
  • $\begingroup$ I am using Mathematica 11.0 and cannot install higher version on windows 7 (it gives error so I need to format and install new windows), For ILP Problem I don;t carry about speed, I can wait even hours, but because of this error I am forced to choose "abort" because it still appear even if I choose "Continue waiting", this error normally appear when I try to make any thing in interface like scroll or only press mouse on any part of the interface, and also appear even if I do not do any thing, For example I leave the computer and return to so the result I see this error, $\endgroup$
    – user81348
    Jun 9, 2022 at 19:53
  • $\begingroup$ what is the possibilities for other algorithms??? I tried all functions for optimization problems and all give this error, for this I need help $\endgroup$
    – user81348
    Jun 9, 2022 at 19:55

0

Reset to default

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge that you have read and understand our privacy policy and code of conduct.

Browse other questions tagged or ask your own question.