How can I install mpmath as an external library for Blender?
Question: I'm interested in trying out sympy with Blender (v2.76, Python 3.4.2 Console,
Windows 8.1). I followed this
[answer](http://blender.stackexchange.com/questions/15453/error-import-
point3d-of-geometry-module-of-sympy0-7-5-in-blender2-71/15513#15513) from
Blender SE, downloaded sympy as a ZIP from Githib, and moved the sympy folder
to C:\Program Files\Blender Foundation\Blender\2.76\python\lib\site-packages.
However, when I opened Blender and tried to import sympy in the Python
Console, I got the following error:

    
    
    >>> import sympy
    Traceback (most recent call last):
      File "<blender_console>", line 1, in <module>
      File "C:\Program Files\Blender Foundation\Blender\2.76\python\lib\site-packages\sympy\__init__.py", line 20, in <module>
        raise ImportError("SymPy now depends on mpmath as an external library. "
    ImportError: SymPy now depends on mpmath as an external library. See http://docs.sympy.org/latest/install.html#mpmath for more information. 
    

I don't know how to install an external library. I tried going to the
[link](http://docs.sympy.org/latest/install.html#mpmath) mentioned in the
ImportError, and I saw `pip install mpmath`. I tried it in cmd, but got this:

    
    
    >pip install mpmath
    Requirement already satisfied (use --upgrade to upgrade): mpmath in c:\anaconda3
    \lib\site-packages
    

I did install Anaconda a while ago, so I guess it makes sense to have this
output. How can I install mpmath as an external library for Blender so I can
import sympy in it?


Answer: You want to install mpmath into blenders python folder, the same as you have
done for sympy.

Your example of running pip was done in a system installed python that is
setup to find the mpmath that you have installed in `c:\anaconda3\lib\site-
packages`

Another option is to use the existing install of mpmath and sympy by adding
your existing path to
[sys.path](https://docs.python.org/3/library/sys.html#sys.path) or adding it
to the `PYTHONPATH` environment variable before you start blender.

