It is also possible to call the C++ version of GeographicLib directly from Python and this directory contains a small example, PyGeographicLib.cpp, which uses boost-python and the Geoid class to convert heights above the geoid to heights above the ellipsoid. More information on calling boost-python, see

https://www.boost.org/doc/libs/release/libs/python

To build and install this interface, do

mkdir BUILD
cd BUILD
cmake -D CMAKE_INSTALL_PREFIX=~/.local ..
make
make install

This assumes that you have installed GeographicLib somewhere that cmake can find it. If you want just to use the version of GeographicLib that you have built in the top-level BUILD directory, include, e.g.,

-D GeographicLib_DIR=../../BUILD

in the invocation of cmake (the directory is relative to the source directory, wrapper/python).

make install installs PyGeographicLib in

~/.local/lib/python2.7/site-packages

which is in the default search path for python 2.7. To convert 20m above the geoid at 42N 75W to a height above the ellipsoid, do

$ python
>>> from PyGeographicLib import Geoid
>>> geoid = Geoid("egm2008-1")
>>> geoid.EllipsoidHeight(42, -75, 20)
-10.671887499999997
>>> help(Geoid.EllipsoidHeight)

Notes:

The geoid data (egm2008-1) should be installed somewhere that GeographicLib knows about.
This prescription applies to Linux machines. Similar steps can be used on Windows and MacOSX machines.
You will need the packages boost-python, boost-devel, python, and python-devel installed.
CMakeLists.txt specifies the version of python to look for (version 2.7). This must match that used in boost-python. To check do, e.g.,
```
ldd /usr/lib64/libboost_python.so
```
CMakeLists.txt looks for a shared-library version of GeographicLib. This is the default with cmake build on non-Windows platforms. On Windows, use the cmake option -D BUILD_SHARED_LIBS=ON to specify building a shared library.

Acknowledgment:

Thanks to Jonathan Takahashi jtakahashi@gmail.com for the sample code in PyGeographicLib.cpp and the commands needed to compile and link this.

Cython

An alternative to boost-python is provided by Cython. Sergey Serebryakov offers the github project

https://github.com/megaserg/geographiclib-cython-bindings

which provides a fast python interface to the geodesic routines.