Cython ImportError: No module named parallel
Question: I am trying to access the new parallel features of Cython 0.15 (using Cython
0.15.1). However, if I try this minimal example (testp.py), taken from
<http://docs.cython.org/src/userguide/parallelism.html>:

    
    
    from cython.parallel import prange, parallel, threadid
    cdef int i
    cdef int sum = 0
    
    for i in prange(n, nogil=True):
        sum += i
    print sum
    

with this setup.py:

    
    
    from distutils.core import setup
    from distutils.extension import Extension
    from Cython.Distutils import build_ext
    import numpy
    
    ext = Extension("testp", ["testp.pyx"], include_dirs=[numpy.get_include()],
                    extra_compile_args=['-fopenmp'], extra_link_args ['-fopenmp'])
    setup(ext_modules=[ext], cmdclass={'build_ext': build_ext})
    

when I `import testp`, Python tells me: `ImportError: No module named
parallel`. And in fact, if I browse the Cython package in the site-packages, I
cannot find any file or directory that is called `parallel`. But I thought it
should be included somewhere in the release? Could someone please clarify for
a confused user?


Answer: You can check all of your python modules in python command-line using:

    
    
    >>> help('modules')
    

And then try to install/reinstall cython using easy_install or pip.

