Opened 4 years ago
Changing model and re-solving can fail with the Clp backend
|Reported by:||AndrewColes||Owned by:||mjs|
|Keywords:||resolve objective fail||Cc:|
If I load a model then do a loop:
1) Objective to maximise column 1, solve, branch & bound
2) Objective to maximise column 2, solve, branch & bound
3) Objective to maximise column 3, solve, branch & bound
then with the OsiClp? backend, the code seems to fail at the first column for which the Objective is worse than on the previous iteration. I can 'fix' the problem by cloning and discarding the model for each loop, but this is rather inefficient. As a comparison, with the OsiCpx? backend, it works just fine as-is.
Testcase attached to demonstrate this. I'm using OSI 0.102 as checked out from the stable branch of the subversion repository.
Thanks for any assistance.