mlx tutorial: interfacing with c++

I followed the 4-step tutorial (matlab 2019b):

https://au.mathworks.com/help/matlab/matlab_external/build-interface-to-matrixoperations-windows.html

A couple of parameters (ReturnCArrays, OverwriteExistingDefinitionFiles) weren't recognizable in clibgen.generateLibraryDefinition(), so I ran it without them.

summary(definematrixlib) and build(definematrixlib) ran fine. But step 4 didn't work:

Unable to resolve the name clib.matrixlib.Mat

and the doc and help matrixlib showed nothing.

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The school example doesn't work either:

https://au.mathworks.com/help/matlab/ref/clibgen.buildinterface.html

After adding this switch to build the library

https://au.mathworks.com/matlabcentral/answers/523497-parsing-error-with-clibgen

I click the link to addpath, but 'help clib.school' returns

clib.school not found.

[Zohar]

Let's start with some basic questions.

What are the final files that are needed to run a plugin?

Which file tells matlab about the interface and new class?

Is there a complete (final) example that comes with matlab?

[Aniket]

I recently followed the Matrix example on Matlab 2019b and it worked fine. The following step is necessary-

Put the compiled library file in the folder with the MATLAB® interface file. Uncomment and execute one of these statements based on your selected compiler.

%copyfile(fullfile(productPath,"win64","mingw64","*.dll"),".","f")
%copyfile(fullfile(productPath,"win64","microsoft","*.dll"),".","f")

Call addpath on the folder containing the interface file.

Answer 1

[Zohar]

In matlab 2021a it works fine.

When you run

matObj = clib.matrixlib.Mat

It looks for a file (in the path) "matrixlibInterface.dll" (which you need to build with the mlx steps), and it needs nothing beyond that.

Note that this file has a dependency on matrixOperations.dll, which needs to be in the path as well. Else, windows will give you the useless error of:

Unable to load interface library: 'matrixlibInterface.dll'. Reason: The

specified module could not be found.

Ensure the C++ dependent libraries for the interface library are added to run-time path.

which means the file couldn't be found or one of its dependencies is missing.

This C++ interface is pretty convenient compared to the C interface, where you need a .mex file per function.