Environment

• Pythonnet version: 3.0.3
• Python version: 3.12.4
• Operating System: Windows 11 23H2
• .NET Runtime: net8.0
• numpy Version: 2.0.0

Details

• Describe what you were trying to get done.

  I am currently migrating from an older undefined pythonnet Version to 3.0.3 with an corresponding upgrade of python from 3.7.9 to 3.12.4.

  We had some C# logic in place which executed python code and took the result of Tuple[nd.ndarray(dtype=int), nd.ndarray(dtype=float)] and converted it from dynamic to concrete types.

I am experiencing issues while converting the nd.ndarray(dtype=int) via (long[])result[0]

---- System.Exception : Cannot convert to System.Int64 array
-------- Microsoft.CSharp.RuntimeBinder.RuntimeBinderException : Cannot convert type 'Python.Runtime.PyObject' to 'long[]'

The nd.ndarray(dtype=float) via (double[])result[1] works as a charme.
Same as when I both return as dtype=float and convert them to double.

My current workaround is iterating over the nd.ndarray(dtype=int) with the size of the result array by calling ToArrayByIteration()

Am I missing something?

• What commands did you run to trigger this issue? If you can provide a
  Minimal, Complete, and Verifiable example
  this will help us understand the issue.

Problematic here is converting "indices" from dtype=int to long in C#. The datatype of the result in C# in Debug view seems to be Int64.

@staticmethoddefmethod(rate:int,data:np.ndarray)->Tuple[np.ndarray,np.ndarray]:ds=int(rate)indices=np.arange(len(data),dtype=int)result_data=np.array(data,dtype=float)n=len(indices )indices=indices [:n*ds:ds]result_data=result_data [:n*ds].reshape(n,ds).mean(axis=1)returnindices ,result_data

Returning dtype=float is not intended but works with the same conversion to double.

@staticmethoddefmethod(rate:int,data:np.ndarray)->Tuple[np.ndarray,np.ndarray]:ds=int(rate)indices=np.arange(len(data),dtype=float)result_data=np.array(data,dtype=float)n=len(indices )indices=indices [:n*ds:ds]result_data=result_data [:n*ds].reshape(n,ds).mean(axis=1)returnindices ,result_data

I left out initialising pythonengine and loading the module in this case.

publicclassWrapper{public(long[]x,double[]y)ExecutePythonMethod(intrate,List<double>data){usingvar_=Py.GIL();varresult=_module.class.method(rate,data);varx=PythonDataConverter.ToArrayByIteration<long>(result[0]);vary=PythonDataConverter.ToArray<double>(result[1]);return(x,y);}}publicstaticclassPythonDataConverter{publicstaticT[]ToArrayByIteration<T>(dynamicarrayFromPython){varsize=(long)arrayFromPython.size;vararray=newT[size];for(vari=0;i<size;i++){array[i]=(T)arrayFromPython[i];}returnarray;}publicstaticT[]ToArray<T>(dynamicarrayFromPython){return(T[])arrayFromPython;}}