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.