Problem importing gurobipy on Linux64

[fabien]

Hello,

I used to have Gurobi 6.5.2 installed on my computer (running on Ubuntu 14.04 LTS), and I recently installed the latest version of Gurobi (7.0.2) to replace it.

I followed the instructions found in the "Gurobi Optimizer Quick Start Guide" during the installation process. Especially:

 - I changed the lines in the .bashrc file so that they point to the new directory corresponding to Gurobi 7.0.2

 - I successfully saved the license key with the command grbgetkey.

 - I entered the command gurobi.sh in the terminal and it works.

I then followed the instructions found on the Gurobi website to install gurobipy with the setup.py file.

When I try the import gurobipy command in Python (2.7.6), I get the following error message:

Traceback (most recent call last):

  File "<stdin>", line 1, in <module>

  File "~/.local/lib/python2.7/site-packages/gurobipy/__init__.py", line 1, in <module>

    from .gurobipy import *

ImportError: libgurobi65.so: cannot open shared object file: No such file or directory

I don't understand this situation for the following reasons:

 - When Gurobi 6.5.2 was installed I could import gurobipy with Python.

 - I recently installed Gurobi 7.0.2 on a Mac computer (first Gurobi installation on this computer) and gurobipy works on this system.

 - From the error message displayed in Python, it is looking for the libgurobi65.so that is not in the directory. Indeed, libgurobi70.so is now in the ~/lib diretory and it should be the one Python opens when importing gurobipy.

 - When I enter the gurobi.sh command in the terminal, I have the following message:

Python 2.7.8 (default, Oct 28 2014, 12:34:31) 

[GCC 4.2.4 (Ubuntu 4.2.4-1ubuntu4)] on linux2

Type "help", "copyright", "credits" or "license" for more information.

Gurobi Interactive Shell (linux64), Version 7.0.2

Copyright (c) 2017, Gurobi Optimization, Inc.

Type "help()" for help

gurobi> 

The version of Python displayed in this message does not seem to match with the one (2.7.6) used when I use Python in the shell.

Can you please help me with that?

Thank you,

Fabien

[fabien]

I solved the problem. I had to get rid off all the previous gurobipy installations (including the one in ~/.local/lib/python2.7/site-packages/) before running setup.py.

[Rahul Bohare]

Hello Fabien, I am having the same problem with gurobi75.so :

Traceback (most recent call last):
  File "<stdin>", line 1, in <module>

  File "/usr/local/lib/python2.7/dist-packages/gurobipy/__init__.py", line 1, in <module>
    from .gurobipy import *
ImportError: libgurobi75.so: cannot open shared object file: No such file or directory

This is my installation of gurobipy, so I do not have any previous gurobipy installations. Can you please help me as to how to install gurobipy successfully? I am working on Ubuntu16.04.
Thanks a lot.

[Daniel Espinoza]

Hi Rahul,

It seems from your output that the dynamic library is not in your LD_LIBRARY_PATH environment library. If you use bash, you can add it by appending this line to your ~/.bashrc

export LD_LIBRARY_PATH=$LD_LIBRARY_PATH:/opt/gurobi751/linux64 

or wherever you installed the library.

Then type 

source ~/.bashrc, or open a new terminal and check that the path is loaded by issuing

echo $LD_LIBRARY_PATH

After that, it should work

Best,

Daniel

[Rahul Bohare]

Hey Daniel, thank you so much for your reply. It worked. :-)

[Daniel Espinoza]

Glad to hear that ;-)

[pope little]

Made a post earlier about how it didn't recognize trying to import Gurobi in python.

Changed the LD_LIBRARY_PATH=/Library/gurobi810/mac64/lib

Now error in Python3 interpreter comes out to be

Any ideas?

[pope little]

This is on macOS Mojave btw

[Daniel Espinoza]

Hi,

That sounds like you are using the wrong version of the library with your python interpreter... did you follow the instructions in the quick start guide?

[Swaprava Nath]

I'm observing this error in 8.1 after my recent install. I tried the method below. It didn't work. I tried the suggestion given in the documentation: http://www.gurobi.com/documentation/8.1/quickstart_linux.pdf under "Building and running the example" -- but make mip1_c++ throws the following errors:

g++ -m64 -g -o mip1_c++ ../c++/mip1_c++.cpp -I../../include/ -L../../lib -lgurobi_c++ -lgurobi81 -lm

/tmp/ccbEODMY.o: In function `main':

/home/swaprava/Downloads/gurobi8.1.0_linux64/gurobi810/linux64/examples/build/../c++/mip1_c++.cpp:25: undefined reference to `GRBModel::addVar(double, double, double, char, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >)'

/home/swaprava/Downloads/gurobi8.1.0_linux64/gurobi810/linux64/examples/build/../c++/mip1_c++.cpp:26: undefined reference to `GRBModel::addVar(double, double, double, char, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >)'

/home/swaprava/Downloads/gurobi8.1.0_linux64/gurobi810/linux64/examples/build/../c++/mip1_c++.cpp:27: undefined reference to `GRBModel::addVar(double, double, double, char, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >)'

/home/swaprava/Downloads/gurobi8.1.0_linux64/gurobi810/linux64/examples/build/../c++/mip1_c++.cpp:35: undefined reference to `GRBModel::addConstr(GRBTempConstr const&, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >)'

/home/swaprava/Downloads/gurobi8.1.0_linux64/gurobi810/linux64/examples/build/../c++/mip1_c++.cpp:39: undefined reference to `GRBModel::addConstr(GRBTempConstr const&, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >)'

/home/swaprava/Downloads/gurobi8.1.0_linux64/gurobi810/linux64/examples/build/../c++/mip1_c++.cpp:45: undefined reference to `GRBVar::get[abi:cxx11](GRB_StringAttr) const'

/home/swaprava/Downloads/gurobi8.1.0_linux64/gurobi810/linux64/examples/build/../c++/mip1_c++.cpp:47: undefined reference to `GRBVar::get[abi:cxx11](GRB_StringAttr) const'

/home/swaprava/Downloads/gurobi8.1.0_linux64/gurobi810/linux64/examples/build/../c++/mip1_c++.cpp:49: undefined reference to `GRBVar::get[abi:cxx11](GRB_StringAttr) const'

/home/swaprava/Downloads/gurobi8.1.0_linux64/gurobi810/linux64/examples/build/../c++/mip1_c++.cpp:56: undefined reference to `GRBException::getMessage[abi:cxx11]() const'

collect2: error: ld returned 1 exit status

Makefile:84: recipe for target 'mip1_c++' failed

make: *** [mip1_c++] Error 1

There isn't any other online support for this problem, hence I'm getting in touch through email. I have installed gurobi properly and installed the license too.

Swaprava

[Swaprava Nath]

Any help to get my Gurobi running will be highly appreciated. 

[Michael Winkler]

HI Swaprava,

I believe you should have opened a different thread for this because it is not connected to this item. The issue is that the C++ compiler depending on there version switch to different ABIs. For that reason we should two different C++ libraries. In your Gurobi installation in the "lib" subdirectory you can find libgurobi_g++4.2.a and libgurobi_g++5.2.a and a softlink libgurobi_c++.a that points to the former. You can change this softlink to point to libgurobi_g++5.2.a and then rerun the make command for mip1_c++. If this still does not work we should the C++ interface code which you can build. For this follow the instructions in the "src/README" file in the Gurobi installation directory.

Best,

Michael