I’ve implemented a neighbourhood search technique wherein I deepcopy the original model, hot-start it and then solve it repeatedly. While the first iteration went smooth, during the second iteration however, I get this error while solving the modified MIP ERROR: LoadError: BoundsError: attempt to a…

Instead of the deepcopy, you should just rebuild the model using createproblem. The upcoming release of JuMP will support constraint deletion which should help this situation a lot. Then you can just delete the cut and add a new one in each iteration to the same model. Some solvers will also suppo…

Hi @varun7rs , can you provide a minimum working example that triggers this bug? It’s a little hard to find out what is going wrong otherwise.

Hi @odow , thanks for your reply. The original problem was too complicated to post. This is a condensed version of the problem I’m solving but I encounter a different error now. The stacktrace seems a little too similar to the previous error however. Just to briefly explain what the heuristic does, …

deepcopy is not intended to be used on JuMP models. It can lead to unexpected behaviour as you observe. Why do you need the copy instead of just using the model p everywhere?

Since I modify model p at every iteration(I add a cut-off constraint which is modified over the course of the heuristic), I wanted to have a different copy of the model. And since I had trouble doing this , I used deepcopy. Is there another way around this problem? For now, I’ve settled with re-buil…

BoundsError when re-solving a model

Specific Domains Optimization (Mathematical)

varun7rs June 30, 2018, 5:51pm 7

Thanks a lot for the help.

Topic		Replies	Views
Strange behavior with deepcopy Optimization (Mathematical) jump	6	1201	May 8, 2019
JuMPv0.21 and deepcopy Optimization (Mathematical) jump , deepcopy	7	995	March 17, 2020
Copying a JuMP model is slower than building it from scratch Optimization (Mathematical) question , jump	6	222	June 26, 2025
Fail to re-add new constraints as a new upper bound of an expression in JuMP model Optimization (Mathematical) question , optimization	2	75	May 12, 2025
Copying a Model? Optimization (Mathematical) jump , copy	5	1145	February 12, 2024

BoundsError when re-solving a model

Related topics