pythonnet 3.1.0-preview2024-03-03

pythonnet is a package that gives .NET programmers ability to integrate Python engine and use Python libraries.

Embedding Python in .NET

• You must set Runtime.PythonDLL property or PYTHONNET_PYDLL environment variable, 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 *nix). Full path may be required.
• 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). You can also access Python objects via PyObject and dervied types instead of using dynamic.
• Use mod.func(args, Py.kw("keywordargname", keywordargvalue)) or mod.func(args, keywordargname: keywordargvalue) to apply keyword arguments.
• Mathematical operations involving python and literal/managed types must have the python object first, eg. np.pi * 2 works, 2 * np.pi doesn't.

Example

using var _ = Py.GIL();

dynamic np = Py.Import("numpy");
Console.WriteLine(np.cos(np.pi * 2));

dynamic sin = np.sin;
Console.WriteLine(sin(5));

double c = (double)(np.cos(5) + sin(5));
Console.WriteLine(c);

dynamic a = np.array(new List<float> { 1, 2, 3 });
Console.WriteLine(a.dtype);

dynamic b = np.array(new List<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.]

Resources

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

.NET Foundation

This project is supported by the .NET Foundation.