Search code examples
pythonnumpycygwin

Cygwin: import numpy error

I am trying to import numpy in Cygwin. I get the following error message.

I have numpy 1.11.2-1, a.k.a. the python2-numpy: Python scientific computing module package, installed through the Cygwin installer. I also have Python 2.7.14-1, a.k.a. the python2: Python 2 language interpreter package also installed through Cygwin. I don't have a local installation of Python on my machine.

$ python
Python 2.7.14 (default, Oct 31 2017, 21:12:13)
[GCC 6.4.0] on cygwin
Type "help", "copyright", "credits" or "license" for more information.
>>> import numpy
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/usr/lib/python2.7/site-packages/numpy/__init__.py", line 142, in <module>
    from . import add_newdocs
  File "/usr/lib/python2.7/site-packages/numpy/add_newdocs.py", line 13, in <module>
    from numpy.lib import add_newdoc
  File "/usr/lib/python2.7/site-packages/numpy/lib/__init__.py", line 8, in <module>
    from .type_check import *
  File "/usr/lib/python2.7/site-packages/numpy/lib/type_check.py", line 11, in <module>
    import numpy.core.numeric as _nx
  File "/usr/lib/python2.7/site-packages/numpy/core/__init__.py", line 14, in <module>
    from . import multiarray
ImportError: No such file or directory

cygcheck:

$ cygcheck -c python2-numpy
Cygwin Package Information
Package              Version        Status
python2-numpy        1.11.2-1       OK

Also, I was able to import numpy in Cygwin on another computer.

There seem to be a number of posts on this but all lacking a solution that works for me. I tried restarting my computer per Not able to import numpy in cygwin, but that did not work.

I have also edited my $PATH variable:

$ echo $PATH
/usr/lib/python2.7/site-packages/numpy/:/usr/lib/python2.7/site-packages/:/usr/bin

The solution:

$ PATH=/usr/lib/lapack:$PATH
Solution

  • Numpy is unable to load the BLAS library, probably as the PATH was redefined to NOT include /usr/lib/lapack or you are not using bash or csh.

    $ cygcheck -l liblapack0
/etc/profile.d/lapack0.csh
/etc/profile.d/lapack0.sh
/usr/lib/lapack/cygblas-0.dll
/usr/lib/lapack/cyglapack-0.dll

    For avoiding collision the NETLIB BLAS shared library is under /usr/lib/lapack and the scripts in /etc/profile.d/ add that directory to the PATH

    $ cat /etc/profile.d/lapack0.sh
LA_PREFIX=/usr
LA_LIBDIR=${LA_PREFIX}/lib
LA_BINDIR=${LA_LIBDIR}/lapack

# Check if the PATH variable is empty or not


if test -n "${PATH}"; then
  # PATH is not empty

  # Check if path is already in PATH
  if ! /bin/echo ${PATH} | /bin/grep -q "${LA_BINDIR}" ; then
    # Path is not already in PATH, append it to PATH
    export PATH="${PATH}:${LA_BINDIR}"
  fi
else
  # PATH is empty
  export PATH="${LA_BINDIR}"
fi

unset LA_PREFIX
unset LA_LIBDIR
unset LA_BINDIR