`cimport numpy` raises error using Cython

Question

I am trying to cimport NumPy into a Python 2.7 shell from a .pyx file, but it keeps giving me the same error:

I made a .pyx file called numpyx just to see if it was part of the bigger code I was running, the file contains:

cimport numpy as np
a = np.arange(0,10)
print 'a= ',a

I get the following error every time:

Traceback (most recent call last):
  File "<pyshell#82>", line 1, in <module>
    import numpyx
  File "C:\Users\Scott\AppData\Roaming\Python\Python27\site-packages\pyximport       \pyximport.py", line 335, in load_module
    self.pyxbuild_dir)
  File "C:\Users\Scott\AppData\Roaming\Python\Python27\site-packages\pyximport\pyximport.py", line 183, in load_module
    so_path = build_module(name, pyxfilename, pyxbuild_dir)
  File "C:\Users\Scott\AppData\Roaming\Python\Python27\site-packages\pyximport\pyximport.py", line 167, in build_module
    reload_support=pyxargs.reload_support)
  File "C:\Users\Scott\AppData\Roaming\Python\Python27\site-packages\pyximport\pyxbuild.py", line 85, in pyx_to_dll
    dist.run_commands()
  File "C:\Python27\lib\distutils\dist.py", line 953, in run_commands
    self.run_command(cmd)
  File "C:\Python27\lib\distutils\dist.py", line 972, in run_command
    cmd_obj.run()
  File "C:\Users\Scott\AppData\Roaming\Python\Python27\site-packages\Cython\Distutils\build_ext.py", line 135, in run
_    build_ext.build_ext.run(self)
  File "C:\Python27\lib\distutils\command\build_ext.py", line 340, in run
    self.build_extensions()
  File "C:\Users\Scott\AppData\Roaming\Python\Python27\site-packages\Cython\Distutils\build_ext.py", line 143, in build_extensions
    self.build_extension(ext)
  File "C:\Python27\lib\distutils\command\build_ext.py", line 499, in build_extension
    depends=ext.depends)
  File "C:\Python27\lib\distutils\ccompiler.py", line 624, in compile
    self._compile(obj, src, ext, cc_args, extra_postargs, pp_opts)
  File "C:\Python27\lib\distutils\cygwinccompiler.py", line 166, in _compile
    raise CompileError, msg
ImportError: Building module failed: ["CompileError: command 'gcc' failed with exit status 1\n"]

I don't understand why it won't work, since it compiles .pyx files fine as long as cimport isn't in them.

If anyone could shed some light on this it would be great!

Answer 1

Well the function your looking for is available in the python package. (I find no reference to linspace in numpy.pxd)

I usually do something along these lines:

import numpy as np
cimport numpy as cnp

def foo(double x):
    cdef cnp.ndarray[cnp.float64_t, ndim=1] y = np.linspace(0, 10, 11)
    # do whatever
    return y