conda installation failure

[pelue]

win10, specific conda environment with python 3.5.6, pip install raysect fails and reports

Installing build dependencies ... done Complete output from command python setup.py egg_info: Traceback (most recent call last): File "C:...\lib\multiprocessing\context.py", line 189, in get_context ctx = _concrete_contexts[method] KeyError: 'fork'

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "<string>", line 1, in <module>
  File "C:\...\pip-install-j71wjq1p\raysect\setup.py", line 8, in <module>
    multiprocessing.set_start_method('fork')
  File "C:\...\lib\multiprocessing\context.py", line 235, in set_start_method
    self._actual_context = self.get_context(method)
  File "C:\...\lib\multiprocessing\context.py", line 227, in get_context
    return super().get_context(method)
  File "C:\...\lib\multiprocessing\context.py", line 191, in get_context
    raise ValueError('cannot find context for %r' % method)
ValueError: cannot find context for 'fork'

any help, please?

[vsnever]

Hi @pelue, Raysect does not work on Windows out of the box. Raysect uses the fork method to create new processes not only at installation, but also at runtime. This minimizes memory usage during parallel computing thanks to copy-on-write paradigm. However, the fork method is supported only by Unix OSes (Linux, MacOS).

You can install Raysect on Windows via the Windows Subsystem for Linux (WSL), https://learn.microsoft.com/en-us/windows/wsl/install. You need WSL version >= 2.0

[pelue]

thank you very much. I will try then and in case I will be back.

[pelue]

I am also trying on an AFS system, still fails. Please see the attached file. Thanks

[vsnever]

I am also trying on an AFS system, still fails. Please see the attached file. Thanks

Raysect is unlikely to work on Python versions older than 3.5. But if you get this error, it looks like you are using a Python version older than 3.4.

[pelue]

I am sorry, I thought to have checked. You are right, the output of python -V is 2.7.5. Thanks

[pelue]

Hello, I managed to install python 3.5.6 as well as cython, numpy, scipy and matplotlib. This is the error I get now:

Traceback (most recent call last): File "/.../lib/python3.5/multiprocessing/pool.py", line 119, in worker result = (True, func(*args, *kwds)) File "/.../lib/python3.5/multiprocessing/pool.py", line 44, in mapstar return list(map(args)) File "/tmp/pip-build-env-zhkuzrkd/lib/python3.5/site-packages/Cython/Build/Dependencies.py", line 1345, in cythonize_one_helper return cythonize_one(*m) File "/tmp/pip-build-env-zhkuzrkd/lib/python3.5/site-packages/Cython/Build/Dependencies.py", line 1321, in cythonize_one raise CompileError(None, pyx_file) Cython.Compiler.Errors.CompileError: raysect/core/math/spatial/kdtree3d.pyx """

The above exception was the direct cause of the following exception:

Traceback (most recent call last):
  File "<string>", line 1, in <module>
  File "/tmp/pip-install-6g4h69d2/raysect/setup.py", line 68, in <module>
    extensions = cythonize(extensions, nthreads=multiprocessing.cpu_count(), force=force, compiler_directives=cython_directives, annotate=annotate)
  File "/tmp/pip-build-env-zhkuzrkd/lib/python3.5/site-packages/Cython/Build/Dependencies.py", line 1145, in cythonize
    result.get(99999)  # seconds
  File "/.../lib/python3.5/multiprocessing/pool.py", line 644, in get
    raise self._value
Cython.Compiler.Errors.CompileError: raysect/core/math/spatial/kdtree3d.pyx

----------------------------------------

Command "python setup.py egg_info" failed with error code 1 in /tmp/pip-install-6g4h69d2/raysect/

I would still appreciate any help. Thanks

[vsnever]

Could you please indicate which version of Cython you have installed?

cython -V

[vsnever]

Also, Raysect 0.8.1 provides binary wheels for Python 3.7–3.9, so if you had a python version in that range, you wouldn't have to compile it yourself.

[pelue]

Hello, the version is 0.28.5. I did not know that there was a better compatibility with Python 3.7 or 3.9 from the raysect or cherab websites. So I can make a conda environment with 3.9 in case. Should I move to Python 3.9 then? Thanks for your help.

[vsnever]

Hello, the version is 0.28.5. I did not know that there was a better compatibility with Python 3.7 or 3.9 from the raysect or cherab websites. So I can make a conda environment with 3.9 in case. Thanks for your help.

Thanks. I can't guarantee that Raysect will compile with Cython version < 0.29.

I think the best way is to setup Python 3.9 environment and run:

pip install cherab

This will install Cherab 1.4 and all its dependencies, including the matching version of Raysect.

[pelue]

Thanks, it worked.