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ValueError: cannot find context for 'fork'

See original GitHub issue

I’m running it on Windows 10. I get the error when running

from pandarallel import pandarallel
pandarallel.initialize()

---------------------------------------------------------------------------
ValueError                                Traceback (most recent call last)
<ipython-input-5-b7dddfb62cf5> in <module>
----> 1 from pandarallel import pandarallel
      2 pandarallel.initialize()

~\Anaconda3\envs\pipeline\lib\site-packages\pandarallel\__init__.py in <module>
      1 __version__ = "1.5.1"
      2 
----> 3 from .pandarallel import pandarallel

~\Anaconda3\envs\pipeline\lib\site-packages\pandarallel\pandarallel.py in <module>
     25 # Python 3.8 on MacOS by default uses "spawn" instead of "fork" as start method for new
     26 # processes, which is incompatible with pandarallel. We force it to use "fork" method.
---> 27 context = get_context("fork")
     28 
     29 # By default, Pandarallel use all available CPUs

~\Anaconda3\envs\pipeline\lib\multiprocessing\context.py in get_context(self, method)
    236             return self._actual_context
    237         else:
--> 238             return super().get_context(method)
    239 
    240     def set_start_method(self, method, force=False):

~\Anaconda3\envs\pipeline\lib\multiprocessing\context.py in get_context(self, method)
    190             ctx = _concrete_contexts[method]
    191         except KeyError:
--> 192             raise ValueError('cannot find context for %r' % method) from None
    193         ctx._check_available()
    194         return ctx

ValueError: cannot find context for 'fork'

Issue Analytics

State:
Created 3 years ago
Comments:5 (1 by maintainers)

Top GitHub Comments

9reactions

om-hbcommented, Sep 21, 2020

I had exactly the same problem with Python 3.6.10 in VS Code on a Windows 10 machine. Could solve it by downgrading pandarallel to version 1.4.8.

1reaction

nalepaecommented, Sep 21, 2020

As written in the Readme, do you use WSL?

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