Marshal double array to MATLAB with IntPtr

I have a .Net library with a method that returns an interface with 2 members:

IntPtr PointerToFirstElement { get; }
int Count { get; }

These allow access to an array of doubles without copying. I want to plot this array in MATLAB by calling the method on the .Net library, but I can't figure out how to create a plottable MATLAB structure from my IntPtr and Count.

Answer 1

[Guillaume]

I don't think matlab has any way to access directly the unmanaged memory pointed to by the IntPtr as that would normally be wrapped in an unsafe block.

All I can think of is going through the marshalling methods to make a copy to managed memory and get that through matlab. However, I'm not experienced enough with that aspect of .Net to be sure it is really going to work:

netarray = NET.createArray('System.Double', yourobject.Count);  %allocate managed array to receive copy of unmanaged data
System.Runtime.InteropServices.Marshal.Copy(yourobject.PointerToFirstElement, netarray, 0, yourobject.Count);   %copy unmanaged to managed
data = double(netarray);   %convert to matlab array

If I got it wrong, it is very likely to crash matlab.

[William Sardar]

Thanks for your input. Shame if I can't access unmanaged memory - this is possible in Python with Numpy! I am trying to avoid doing a copy for performance reasons. What's more, it looks like you can access unmanaged memory when calling into a native (e.g. C++) dll, with the libpointer class.