Trouble Installing CyLP and CBC from Source

[spkelle2]

Hi everyone,

I am trying to install CyLP (v0.91.5) from source using CBC (2.10) which has also been installed from source. I run pip install --no-build-isolation . and I am told Successfully installed cylp-0.91.5.

Sounds great.

However, I run into issues when I try to import CyLP in an interpreter. (As a side note, when I install CBC from conda, installing CyLP from source works as expected and I get no issues importing any of the objects. Unfortunately, for my application, I need to be able to use CBC installed from source). When I open up my interpreter (from pycharm) inside the conda environment the setup suggests to build and I call from cylp.cy.CyClpSimplex import CyClpSimplex, I get the following error:

Traceback (most recent call last):
  File "/Applications/PyCharm.app/Contents/plugins/python/helpers/pydev/_pydev_bundle/pydev_import_hook.py", line 21, in do_import
    module = self._system_import(name, *args, **kwargs)
  File "/Users/sean/opt/miniconda3/envs/CyLP/lib/python3.10/site-packages/cylp/cy/__init__.py", line 1, in <module>
    from .CyCoinIndexedVector import CyCoinIndexedVector
  File "/Applications/PyCharm.app/Contents/plugins/python/helpers/pydev/_pydev_bundle/pydev_import_hook.py", line 21, in do_import
    module = self._system_import(name, *args, **kwargs)
ImportError: dlopen(/Users/sean/opt/miniconda3/envs/CyLP/lib/python3.10/site-packages/cylp/cy/CyCoinIndexedVector.cpython-310-darwin.so, 0x0002): symbol not found in flat namespace '__ZN9CoinError12printErrors_E'

When I open my interpreter from the command line within my conda environment and call from cylp.cy.CyClpSimplex import CyClpSimplex, it looks like I get a similar error:

Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/Users/sean/Documents/school/phd/research/CyLP/cylp/cy/__init__.py", line 1, in <module>
    from .CyCoinIndexedVector import CyCoinIndexedVector
ModuleNotFoundError: No module named 'cylp.cy.CyCoinIndexedVector'

Would anyone be able to advise how I can get CyLP to run when it and CBC are installed from source?

If it helps, here are the steps on my machine (macOS Monterrey 12.4) that caused the error:

• Install CBC
  • cd ~/
  • git clone https://github.com/coin-or/coinbrew coin-or
  • cd coin-or
  • ./coinbrew fetch Cbc@2.10 --skip="ThirdParty/Blas ThirdParty/Lapack ThirdParty/Metis ThirdParty/Mumps" --no-prompt
  • ./coinbrew build Cbc --skip="ThirdParty/Blas ThirdParty/Lapack ThirdParty/Metis ThirdParty/Mumps" --no-prompt --prefix=/Users/sean/coin-or/dist --enable-debug
  • add export DYLD_LIBRARY_PATH=/Users/sean/coin-or/dist/lib to ~/.bashrc
  • add export PKG_CONFIG_PATH=/Users/sean/coin-or/dist/lib/pkgconfig to ~/.bashrc
  • source ~/.bashrc
• Create Conda Environment
  • cd ~/
  • conda create -n CyLP cython numpy pkg-config scipy
  • conda activate CyLP
• Install CyLP
  • git clone git@github.com:coin-or/CyLP.git
  • cd CyLP
  • pip install --no-build-isolation .
• Import CyClpSimplex in command line interpreter
  • python
  • from cylp.cy.CyClpSimplex import CyClpSimplex
• Import CyClpSimplex in PyCharm interpreter
  • Open PyCharm
  • Set interpreter to CyLP environment's python
  • call from cylp.cy.CyClpSimplex import CyClpSimplex in Python Console

[spkelle2]

So I reran the above with conda create and pip install both verbose (-vv argument appended to each). I found I was getting many warnings that CBC, CGL, CLP, etc. were built for arm (bc I have a mac with M1 chips) but CyLP is building for intel thus they can't link. Diving into it a little deeper, turns out CyLP was building for intel because all python packages build for intel by default in conda, as explained here. I updated the conda command to be CONDA_SUBDIR=osx-arm64 conda create -v -n CyLP cython numpy pkg-config scipy.

After this, I then needed to add the --enable-shared flag to coinbrew's build for the shared libraries to link correctly when building. Then, CyLP built as expected. In summary, I had to do the following to build CyLP with CBC built from source on my machine:

• Install CBC
  • cd ~/
  • git clone https://github.com/coin-or/coinbrew coin-or
  • cd coin-or
  • ./coinbrew fetch Cbc@2.10 --skip="ThirdParty/Blas ThirdParty/Lapack ThirdParty/Metis ThirdParty/Mumps" --no-prompt
  • ./coinbrew build Cbc --skip="ThirdParty/Blas ThirdParty/Lapack ThirdParty/Metis ThirdParty/Mumps" --no-prompt --prefix=/Users/sean/coin-or/dist --enable-debug --enable-shared
  • add export DYLD_LIBRARY_PATH=/Users/sean/coin-or/dist/lib to ~/.bashrc
  • add export PKG_CONFIG_PATH=/Users/sean/coin-or/dist/lib/pkgconfig to ~/.bashrc
  • source ~/.bashrc
• Create Conda Environment
  • cd ~/
  • CONDA_SUBDIR=osx-arm64 conda create -n CyLP cython numpy pkg-config scipy
  • conda activate CyLP
• Install CyLP
  • git clone git@github.com:coin-or/CyLP.git
  • cd CyLP
  • pip install --no-build-isolation .