Errors when installed with pip

[Joao-Dionisio]

I'm getting errors when trying to solve a simple problem, depending on whether I installed pygcgopt with pip or with conda. Here is the problem: test.zip

When installed with pip (it keeps looping):

When installed with conda:

 time | node  | left  |SLP iter|MLP iter|LP it/n| mem |mdpt |ovars|mvars|ocons|mcons|mcuts|  dualbound   | primalbound  |  deg   |  gap   
p  0.0s|     1 |     0 |      0 |      0 |     - |2231k|   0 |  20 |   0 |  13 |   0 |   0 | 0.000000e+00 | 4.000000e+00 |   --   |    Inf 
p  0.0s|     1 |     0 |      0 |      0 |     - |2231k|   0 |  20 |   0 |  13 |   0 |   0 | 0.000000e+00 | 3.000000e+00 |   --   |    Inf 
p  0.0s|     1 |     0 |      0 |      0 |     - |2230k|   0 |  20 |   0 |  13 |   0 |   0 | 0.000000e+00 | 2.000000e+00 |   --   |    Inf 
   0.0s|     1 |     0 |      0 |      0 |     - |2228k|   0 |  20 |   0 |  13 |   0 |   0 | 2.000000e+00 | 2.000000e+00 |   --   |   0.00%

SCIP Status        : problem is solved [optimal solution found]
Solving Time (sec) : 0.03
Solving Nodes      : 1
Primal Bound       : +2.00000000000000e+00 (3 solutions)
Dual Bound         : +2.00000000000000e+00
Gap                : 0.00 %

There are also times when I get segfaults with pip:

>>> from pygcgopt import Model
>>> m = Model()
>>> m.optimize()
[1]    89725 segmentation fault (core dumped)  python

A difference between the two is that with conda, pygcgopt install pyscipopt v5.3.0, while with pip, it installs v.5.5.0. This version was released last week, although I don't see what was added that could cause problems. In either case, it might be better not to pip install the latest release of pyscipopt, but rather something we know is working.

[CodingTil]

Might be related to #42

See https://scipopt.github.io/PyGCGOpt/INSTALL.html for an overview of which versions of pyscipopt pygcgopt is compatible with.