Decoder for primitive types in ctypes module #1276

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1. lostmsu

   added

   enhancement

   on Nov 9, 2020
2. fractus commented on Jul 29, 2022

   

   fractus

   on Jul 29, 2022

   Last edited by fractus

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   A realted topic is numpy and pandas types (any instance of np.ndarray, and pd.core.arrays.ExtensionArray. I tried the following but it didn't work - it's not even triggered, I guess because it's primitives?

       public class NumpyDecoder : IPyObjectDecoder
       {
           public bool CanDecode(PyType objectType, Type targetType)
           {
               return targetType == typeof(double) && objectType.Name.StartsWith("numpy.float64");
           }
   
           public bool TryDecode<T>(PyObject pyObj, out T value)
           {
               value = (T)(object)pyObj.GetAttr("item").As<double>();
               return true;
           }
       }

   Python.Runtime.PyObjectConversions.RegisterDecoder(NumpyDecoder())
   xs = np.array([1.0, 2.0], dtype=np.float64)
   lst = List[Double]()
   lst.Add(xs[0])        # Fails
   lst.Add(xs[0].item()) # Works

   This is also reported in #1887

   See also https://stackoverflow.com/questions/9452775/converting-numpy-dtypes-to-native-python-types

   👍React with 👍1Reacted by Tarudro
3. filmor

   removed

   enhancement

   on Aug 12, 2022
4. lostmsu

   added

   hacktoberfest

   on Sep 16, 2022
5. lostmsu

   self-assigned this

   on Sep 16, 2022