Python.NET is a package that gives Python programmers nearly seamless integration with the .NET Common Language Runtime (CLR) and provides a powerful application scripting tool for .NET developers. It allows Python code to interact with the CLR, and may also be used to embed Python into a .NET application.

Python.NET allows CLR namespaces to be treated essentially as Python packages.

importclrfromSystemimportStringfromSystem.Collectionsimport*

To load an assembly, use the AddReference function in the clr module:

importclrclr.AddReference("System.Windows.Forms") fromSystem.Windows.FormsimportForm

By default, Mono will be used on Linux and macOS, .NET Framework on Windows. For details on the loading of different runtimes, please refer to the documentation.

If .NET Core is installed in a default location or the dotnet CLI tool is on the PATH, loading it instead of the default (Mono/.NET Framework) runtime just requires setting either the environment variable PYTHONNET_RUNTIME=coreclr or calling pythonnet.load explicitly:

frompythonnetimportloadload("coreclr") importclr

• You must set Runtime.PythonDLL property or PYTHONNET_PYDLL environment variable starting with version 3.0, otherwise you will receive BadPythonDllException (internal, derived from MissingMethodException) upon calling Initialize. Typical values are python38.dll (Windows), libpython3.8.dylib (Mac), libpython3.8.so (most other Unix-like operating systems).
• Then call PythonEngine.Initialize(). If you plan to use Python objects from multiple threads, also call PythonEngine.BeginAllowThreads().
• All calls to python should be inside a using (Py.GIL()){/* Your code here */} block.
• Import python modules using dynamic mod = Py.Import("mod"), then you can call functions as normal, eg mod.func(args).
• Use mod.func(args, Py.kw("keywordargname", keywordargvalue)) or mod.func(args, keywordargname: keywordargvalue) to apply keyword arguments.
• All python objects should be declared as dynamic type.
• Mathematical operations involving python and literal/managed types must have the python object first, eg. np.pi * 2 works, 2 * np.pi doesn't.

staticvoidMain(string[]args){PythonEngine.Initialize();using(Py.GIL()){dynamicnp=Py.Import("numpy");Console.WriteLine(np.cos(np.pi*2));dynamicsin=np.sin;Console.WriteLine(sin(5));doublec=(double)(np.cos(5)+sin(5));Console.WriteLine(c);dynamica=np.array(newList<float>{1,2,3});Console.WriteLine(a.dtype);dynamicb=np.array(newList<float>{6,5,4},dtype:np.int32);Console.WriteLine(b.dtype);Console.WriteLine(a*b);Console.ReadKey();}}

Output:

1.0-0.958924274663-0.6752620892 float64 int32 [6.10.12.]

Information on installation, FAQ, troubleshooting, debugging, and projects using pythonnet can be found in the Wiki:

https://github.com/pythonnet/pythonnet/wiki

Mailing list

https://mail.python.org/mailman/listinfo/pythondotnet

Chat

https://gitter.im/pythonnet/pythonnet

This project is supported by the .NET Foundation.