Prerequisites

Verify that you have met the system requirements for using MATLAB Compiler SDK and running Python applications. For details, see MATLAB Compiler SDK Python Target Requirements.

End users of compiled artifacts without access to MATLAB must install MATLAB Runtime. Artifacts built with MATLAB Compiler SDK require a matching version of MATLAB Runtime at the same update level or newer. You can include MATLAB Runtime in an installer for your Python package or install it separately. For details, see Download and Install MATLAB Runtime.

Create Function in MATLAB

Write MATLAB code that you intend to call in your target language application. Your MATLAB code must follow certain guidelines in order to be deployed. For more details, see Write Deployable MATLAB Code.

For this example, suppose your company's cost function, which represents the total cost associated with managing an inventory, is defined as follows:

You can use the MATLAB function fminsearch to find the order quantity Q that minimizes the total cost C(Q). Create a function named fms.m that takes an initial guess for order quantity, annual demand, cost per order, holding cost per unit per year, and purchase cost per unit and outputs the optimal order quantity and cost.

function [Q_optimal, cost_optimal] = fms(Q_initial_guess, D, S, H, P)
cost_function = @(Q) D/Q * S + Q/2 * H + D * P;
[Q_optimal, cost_optimal] = fminsearch(cost_function, Q_initial_guess)
end

Create Sample MATLAB Script

MATLAB Compiler SDK can generate sample code in the target language that demonstrates how to call a MATLAB exported function. You can use the samples to implement your own application or to test the compiled artifact. For more details, see Create Sample Code to Call Exported Function.

Create a MATLAB sample script that calls your function with defined input values. Save the following code in a sample file named fmsSample1.m.

% Sample script to demonstrate execution of function [Q_optimal, cost_optimal] = fms(Q_initial_guess, D, S, H, P)
Q_initial_guess = 100; % Initialize Q_initial_guess here
D = 10000; % Initialize D here
S = 50; % Initialize S here
H = 0.5; % Initialize H here
P = 10; % Initialize P here
[Q_optimal, cost_optimal] = fms(Q_initial_guess, D, S, H, P)

After packaging, the generated Python sample code calls your exported function using the same input values as in the corresponding MATLAB sample file.

Package MATLAB Code into Deployable Archive

You can build deployable archives at the MATLAB command line or using a graphical interface. For information on choosing which packaging method to use, see Choose Deployment Option.

For this example, build a Python package using the compiler.build.pythonPackage function.

Install and Run Generated Sample Application

After creating your Python package, you can call the fms function from a Python application. For information on creating applications that call packaged MATLAB functions, see Integrate Artifact with Target Language Application.

This example uses the sample Python code OptimizepythonPackage\samples\fmsSample1.py generated during packaging. You can use this sample application code as a guide to write your own Python application.

#!/usr/bin/env python
"""
Sample script that uses the Optimize package created using
MATLAB Compiler SDK.

Refer to the MATLAB Compiler SDK documentation for more information.
"""

import Optimize
# Import the matlab module only after you have imported 
# MATLAB Compiler SDK generated Python modules.
import matlab

try:
    my_Optimize = Optimize.initialize()
except Exception as e:
    print('Error initializing Optimize package\\n:{}'.format(e))
    exit(1)

try:
    Q_initial_guessIn = matlab.double([100], size=(1, 1))
    DIn = matlab.double([10000], size=(1, 1))
    SIn = matlab.double([50], size=(1, 1))
    HIn = matlab.double([0.5], size=(1, 1))
    PIn = matlab.double([10], size=(1, 1))
    Q_optimalOut, cost_optimalOut = my_Optimize.fms(Q_initial_guessIn, DIn, SIn, HIn, PIn, nargout=2)
    print(Q_optimalOut, cost_optimalOut, sep='\n')
except Exception as e:
    print('Error occurred during program execution\\n:{}'.format(e))

my_Optimize.terminate()

The Python sample application does the following:

At the system command prompt, navigate to the MagicSquarePkgpythonPackage folder. Install the Optimize package using the python command.

python -m pip install .

For more information on installing Python packages, see Install and Import MATLAB Compiler SDK Python Packages.

If you have installed MATLAB Runtime, you can run the application at the system command prompt. For testing purposes, you can also run the command in the MATLAB Command Window by preceding the command with the ! operator.

python fmsSample1.py

The Python sample application returns the same output as the sample MATLAB script.

1414.2135620117188 
100707.10678118655