pythonnet - Python for .NET

Python for .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.

Calling .NET code from Python

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

import clr
from System import String
from System.Collections import *

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

import clr
clr.AddReference("System.Windows.Forms")
from System.Windows.Forms import Form

Embedding Python in .NET

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)) 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.

Example

static void Main(string[] args)
{
    using (Py.GIL())
    {
        dynamic np = Py.Import("numpy");
        Console.WriteLine(np.cos(np.pi * 2));

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

        double c = np.cos(5) + sin(5);
        Console.WriteLine(c);
        /* this block is temporarily disabled due to regression #249
        dynamic a = np.array(new List<float> { 1, 2, 3 });
        Console.WriteLine(a.dtype);

        dynamic b = np.array(new List<float> { 6, 5, 4 }, Py.kw("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.]