Problem read from MPS is solved incorrectly

[mkturtledude]

(All files I refer to are attached here)

I'm trying to solve the problem in mkt.mps. If I solve it using CBC on the command line, it takes about 2 minutes and it finds a solution with value -170 (see cbc-output.txt).

However, if I solve it using PuLP as in example.py, it terminates immediately and PuLP claims to have found a solution of value 0. See pulp-output.txt.

Could it be a problem with reading the MPS file? I found issue https://github.com/coin-or/pulp/issues/459, but I have no way of telling whether it's the same bug.

As you can see in the logs, PuLP is using CBC version 2.10.5, and on the command line I used 2.10.3. The PuLP version I'm using is 2.6.0.

Useful extra information

The info below often helps, please fill it out if you're able to. :)

What operating system are you using?

• [ ] Windows: ( version: ___ )
• [x] Linux: ( _distro:_Ubuntu 20.04 )
• [ ] Mac OS: ( version: ___ )
• [ ] Other: ___

I'm using python version:

• [ ] 2.7
• [ ] 3.4
• [ ] 3.5
• [ ] 3.6
• [x] Other: 3.10_

I installed PuLP via:

• [ ] pypi (python -m pip install pulp)
• [ ] github (python -m pip install -U git+https://github.com/coin-or/pulp)
• [x] Other: ___ (conda?)

Did you also

• [ ] Tried out the latest github version: https://github.com/coin-or/pulp
• [x] Searched for an existing similar issue: https://github.com/coin-or/pulp/issues?utf8=%E2%9C%93&q=is%3Aissue%20

[mkturtledude]

Any progress on this?