Galsim installation issue

[sfarrens]

Hi @tobias-liaudat,

I have encountered an issue with the current Galsim installation used by MCCD.

MCCD Issue

When installing MCCD from PyPi,

pip install mccd

Galsim is installed via pip as a dependency. Then when attempting to verify the current version of MCCD,

python -c "import mccd; print(mccd.__version__)"

I get the following errors:

macOS

Traceback (most recent call last):
  File "<string>", line 1, in <module>
  File "/Users/sfarrens/Documents/Library/miniconda3/envs/mccd/lib/python3.7/site-packages/mccd/__init__.py", line 11, in <module>
    from .mccd import MCCD, mccd_quickload
  File "/Users/sfarrens/Documents/Library/miniconda3/envs/mccd/lib/python3.7/site-packages/mccd/mccd.py", line 22, in <module>
    import galsim as gs
  File "/Users/sfarrens/Documents/Library/miniconda3/envs/mccd/lib/python3.7/site-packages/galsim/__init__.py", line 112, in <module>
    from .position import Position, PositionI, PositionD
  File "/Users/sfarrens/Documents/Library/miniconda3/envs/mccd/lib/python3.7/site-packages/galsim/position.py", line 19, in <module>
    from . import _galsim
ImportError: dlopen(/Users/sfarrens/Documents/Library/miniconda3/envs/mccd/lib/python3.7/site-packages/galsim/_galsim.cpython-37m-darwin.so, 2): Library not loaded: @rpath/libgalsim.2.2.dylib
  Referenced from: /Users/sfarrens/Documents/Library/miniconda3/envs/mccd/lib/python3.7/site-packages/galsim/_galsim.cpython-37m-darwin.so
  Reason: image not found

CentOS Linux

Traceback (most recent call last):
  File "<string>", line 1, in <module>
  File "/home/sfarrens/.conda/envs/mccd/lib/python3.7/site-packages/mccd/__init__.py", line 11, in <module>
    from .mccd import MCCD, mccd_quickload
  File "/home/sfarrens/.conda/envs/mccd/lib/python3.7/site-packages/mccd/mccd.py", line 22, in <module>
    import galsim as gs
  File "/home/sfarrens/.conda/envs/mccd/lib/python3.7/site-packages/galsim/__init__.py", line 112, in <module>
    from .position import Position, PositionI, PositionD
  File "/home/sfarrens/.conda/envs/mccd/lib/python3.7/site-packages/galsim/position.py", line 19, in <module>
    from . import _galsim
ImportError: libgalsim.so.2.2: cannot open shared object file: No such file or directory

ShapePipe Issue

This also creates an issue for ShapePipe (in particular on Candide, which uses CentOS Linux). ShapePipe installs Galsim from conda-forge, which a) allows MCCD to work fine but b) creates a conflict between the two Galsim installations on certain systems.

Proposed Solution

I recommend removing Galsim from your requirements.txt and making an new release of MCCD. This will resolve the ShapePipe issues.

With regards to the stand-alone MCCD installation, I think you can include a note that MCCD requires Galsim but it would be better to install this from source or via Conda.

[tobias-liaudat]

Thanks @sfarrens I'll look at it and make a release to fix this issue and also #2

[tobias-liaudat]

Once the issue in the ModOpt package is handled , so that I can solve the issue #2 I will make a new release.

[tobias-liaudat]

This issue is solved.