# A Python interface to GeNN
PyGeNN wraps the C++ GeNN API using SWIG, allowing GeNN to be used either directly from Python or as a backend for higher-level Python APIs such as [PyNN](https://github.com/genn-team/pynn_genn). Building PyGeNN is a little involved so we recommend installing a prebuilt binary wheel from our Releases page or direct from our [build server](https://gen-ci.inf.sussex.ac.uk/job/GeNN/job/genn/).

### Installing PyGeNN from binary wheels
 - Select a suitable wheel from the Releases page (all wheels are build for CUDA 10 except for on Mac OS which is built for CUDA 9). For example, if you have a Linux system with Python 3.7 you would pick ``pygenn-0.2.1-cp37-cp37m-linux_x86_64.whl``. If you do not have CUDA installed, ignore the CUDA version and pick the wheel that otherwise matches your platform.
 - Install the wheel using pip ``pip install pygenn-0.2.1-cp37-cp37m-linux_x86_64.whl``
 
### Installing PyGeNN from source on Linux or Mac OSX
 - Either download the latest release of GeNN and extract into your home directory or clone using git from https://github.com/genn-team/genn
 - Navigate to the GeNN directory and build a dynamic library version of GeNN, directly into the PyGeNN directory using ``make DYNAMIC=1 LIBRARY_DIRECTORY=`pwd`/pygenn/genn_wrapper/``
 - Build the Python extension with setup tools using ``python setup.py develop`` command
 
### Installing PyGeNN from source on Windows
 - Ensure that you have at least Python 3.5 and Visual Studio 2015 installed (extensions for earlier versions of Python cannot be built using any versions of Visual Studio new enough to support C++11). These instructions assume that the Anaconda platform was used to install Python, but it _should_ be possible to install PyGeNN using suitable versions of Python installed in different way (please let us know if you suceed in doing so!)
 - This process requires a command prompt with the environment correctly configured for both Visual Studio **and** Anaconda. To create one, launch an "x64 Native Tools Command Prompt" from your chosen version of Visual Studio's start menu folder and _activate_ your chosen version of Anaconda by running the ``activate.bat`` in its ``Scripts`` directory. For example, if your user is called "me" and Anaconda is installed in your home directory, you would run ``c:\Users\Me\Anaconda3\Scripts\activate.bat c:\Users\Me\Anaconda3``.
 - From this command prompt, install SWIG using the ``conda install swig`` command.
 - Navigate to the GeNN directory and build GeNN as a dll using ``msbuild genn.sln /t:Build /p:Configuration=Release_DLL`` (if you don't have CUDA installed, building the CUDA backend will fail but it should still build the CPU backend).
 - Copy the newly built DLLs into pygenn using ``copy /Y lib\genn*Release_DLL.* pygenn\genn_wrapper``
 - Build the Python extension with setup tools using ``python setup.py develop`` command