It looks like your default Python installation may not be the Anaconda Python, and your default Python has not been updated with Gurobi 8.1.1. When you type

which python

at a Terminal command line what do you get?

If from that same command line, you change to the /Library/gurobi811/mac64/ directory and run

python setup.py install

what happens?

Thanks,

Gwyneth

Hi Gwyneth,

When I type "which python" I got:

Last login: Wed Sep 25 00:02:53 on ttys000

MacBook-Pro-de-Fernando:~ drfernando$which python /anaconda3/bin/python And when I change to the directory /Library/gurobi811/mac64/ and type " python setup.py install I got: MacBook-Pro-de-Fernando:mac64 drfernando$ python setup.py install

running install

running build

running build_py

creating build

creating build/lib

creating build/lib/gurobipy

copying lib/python3.6/gurobipy/__init__.py -> build/lib/gurobipy

copying lib/python3.6/gurobipy/gurobipy.so -> build/lib/gurobipy

running install_lib

creating /anaconda3/lib/python3.6/site-packages/gurobipy

copying build/lib/gurobipy/gurobipy.so -> /anaconda3/lib/python3.6/site-packages/gurobipy

copying build/lib/gurobipy/__init__.py -> /anaconda3/lib/python3.6/site-packages/gurobipy

byte-compiling /anaconda3/lib/python3.6/site-packages/gurobipy/__init__.py to __init__.cpython-36.pyc

running install_egg_info

Writing /anaconda3/lib/python3.6/site-packages/gurobipy-8.1.1-py3.6.egg-info

removing /Library/gurobi811/mac64/build

MacBook-Pro-de-Fernando:mac64 drfernando$Thanks, Fernando Thanks for trying that. What do you see when you run echo$PYTHONSTARTUP

It looks like this might be an environment variable that has not been updated for some reason.

Nothing happens:

MacBook-Pro-de-Fernando:mac64 drfernando$echo$PYTHONSTARTUP

MacBook-Pro-de-Fernando:mac64 drfernando$echo$PYTHONSTARTUP

MacBook-Pro-de-Fernando:mac64 drfernando$Thanks for sending that. I think I see the problem now. Can you try which gurobi.sh and then send the contents of that file? Here is: MacBook-Pro-de-Fernando:mac64 drfernando$ which gurobi.sh

/anaconda3/bin/gurobi.sh

MacBook-Pro-de-Fernando:mac64 drfernando$Can you send the contents of that file? I suspect there is a PYTHONSTARTUP variable in it that points to the wrong directory for Gurobi. Also, are you sure that the example you ran in Acaconda used Gurobi 8.1.1? Thanks. The content is: #!/bin/sh export PYTHONPATH=/Library/gurobi801/mac64/lib export PYTHONSTARTUP=/Library/gurobi801/mac64/lib/gurobi.py /usr/bin/python2.7 "$@"

I´m not sure if I'm running 801 or 811. I've never had this problem before. But it seems that Gurobi is faster. Before the installation of Gurobi 811, I found the response in 300 seconds, now the solution is found in just 40 seconds.

Ok, so I see that gurobi.sh is still pointing to the 8.0.1 installation.

Please edit this file to point to gurobi811 instead of gurobi801, and let me know if that works.

Thanks.

Thanks so much Gwyneth, it worked.

So the issue is solved.

Best regards,

Fernando

Hi Fernando -

Glad to hear it! Thanks for letting me know. I have never seen this issue before!

Happy gurobi-ing!

Gwyneth

I'm using Gurobi Solver since 2016 (Gurobi 6) and I´ve never had this problem. Thanks again for your help.