How to run Matlab generated .DLL files from Python

I have written a simple test code as shown below:

function out = test(a,b)
    out = a+b;
end

Then I have created .DLL file from MATLAB-> APPS -> library compiler -> c Shared Library.

Then I have tried to run it from Python. Here is my test code -

import ctypes
mydll = ctypes.cdll.LoadLibrary("test.dll")
a = 12
b = 100
c = mydll.test(a,b)

I expected to get 112. Instead I am getting following error -

AttributeError: function 'test' not found

I am using Matlab 2021a and have already installed Matlab runtime compiler v910. I think I need to invoke it from Python but don't know how to do this.

Can anyone suggest me how can I call Matlab generated .DLL file from Python?

TIA

[Kojiro Saito]

Just a question. Why not compiling m file to Python package? With Library Compiler, you can create Python module and it's easier to use from Python.

[Patiala Ghos]

Hi,

Here are two things that I need to take care of –

1. I need to protect my code so that the end-user cannot change it easily. That’s why I want to convert it to a binary file. So, I chose to convert it to a .dll file. Now, as for the Python package, as far as I know, it is converted to .ctf format. I think .ctf format also converts to a binary file but I am sure.
2. For my project, processing time is a concerning issue. That’s why I need to know which one is the faster way of running Matlab code in python – converting to .dll or converting to a python package.

Thank you.

[cr]

There could be reasons why one would want to generate c shared lib for use in python. Licence is one. I have compiler lic and 2014b give me a way to output dll. To generate python libs I need another expensive licence. I have never been able to make dll work from C/C++

Answer 1

[Yongjian Feng]

Try to call your dll from a C program first, to make sure it actually works?

[Mark Magdaleno]

Does this mean the python syntax is correct as indicated? If not can you supply know to work python syntax.

Thanks

Answer 2

[Georgy Gilyarovskiy]

I have relative question:

import ctypes
FileName = 'get_frame.dll'
mydll = ctypes.CDLL(FileName)
i = ctypes.c_int32(5)
s = ctypes.c_int32(32)
a = ctypes.create_unicode_buffer(1024)
mydll.get_frame(i, s, ctypes.byref(a))

This code gives me the following error:

OSError: exception: access violation reading 0x0000000000000000

I suppose that it's related to my python. It's probably 64-bit version.

Do you have any ideas how to solve this problem properly?

[Pratyush]

Were you able to resolve your issue?