MATLAB: Is it possible to import and use third party matlab functions/packages in python

enginejarjavaMATLABmatlab engine apipython

I would like to call functions from packages that are imported in Matlab in Python using the MATLAB Engine API for Python. The import/setup work for the package I want to use is contained in load_javaplex.m:
% This script prepares the javaplex library for use
clc; clear all; close all;
%clear import;
javaaddpath('./lib/javaplex.jar');
import edu.stanford.math.plex4.*;
javaaddpath('./lib/plex-viewer.jar');
import edu.stanford.math.plex_viewer.*;
cd './utility';
addpath(pwd);
cd '..';
fprintf('DONE');
% This last line calls a function to test the library
api.Plex4.createExplicitSimplexStream()
In Python I tried the following:
import matlab.engine
eng = matlab.engine.start_matlab()
# prepare javaplex library for use
eng.load_javaplex(nargout=0)
eng.api.Plex4.createExplicitSimplexStream()
When the load_javaplex.m runs it successfully calls api.Plex4.createExplicitSimplexStream(), so we know the package is working in Matlab. But calling eng.api.Plex4.createExplicitSimplexStream() results in an undefined function error (output from running the Python code above):
DONE
ans =
edu.stanford.math.plex4.streams.impl.ExplicitSimplexStream@5e894fec
Undefined function or variable 'api.Plex4.createExplicitSimplexStream'.
Traceback (most recent call last):
  File "/Users/alex/PycharmProjects/SeniorResearchProject/Code/sandbox/test2.py", line 6, in <module>
    eng.api.Plex4.createExplicitSimplexStream()
  File "/Users/alex/anaconda/lib/python2.7/site-packages/matlab/engine/matlabengine.py", line 84, in __call__
    _stderr, feval=True).result()
  File "/Users/alex/anaconda/lib/python2.7/site-packages/matlab/engine/futureresult.py", line 68, in result
    return self.__future.result(timeout)
  File "/Users/alex/anaconda/lib/python2.7/site-packages/matlab/engine/fevalfuture.py", line 82, in result
    self._result = pythonengine.getFEvalResult(self._future,self._nargout, None, out=self._out, err=self._err)
matlab.engine.MatlabExecutionError: Undefined function or variable 'api.Plex4.createExplicitSimplexStream'.
Process finished with exit code 1
Is there a way to call these third party functions from Python?

Best Answer

It looks like your problem is with import. I don't think the import that executes in your script, load_javaplex, is available when you try to call createExplicitSimplexStream. Try using the full name instead of the shortened name. I would guess that the full name is edu.stanford.math.plex4.api.Plex4.createExplicitSimplexStream. Example:
% Use the full name
eng.edu.stanford.math.plex4.api.Plex4.createExplicitSimplexStream()
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