Error using Python with Matlab: matlab.eng​ine.Matlab​ExecutionE​rror: OOPS is not supported

I am trying to learn how to use Python and Matlab together. I wrote a script just to practice a simple lsqcurvefit of some simple generated data. I keep getting this error for line 20: matlab.engine.MatlabExecutionError: OOPS is not supported. I haven't been able to find an answer to this problem. What is wrong with using matlab.inline this way? I am using Python IDLE version 3.9.13 and Matlab version R2023a.

import matlab.engine

import numpy as np

# Start MATLAB engine

matlab = matlab.engine.start_matlab()

# Generate sample data

x = np.linspace(0, 10, 100)

y = 2 * np.sin(x) + np.random.normal(0, 0.5, size=len(x))

# Convert data to 1D arrays

x = np.ravel(x)

y = np.ravel(y)

# Convert data to MATLAB arrays

x_matlab = matlab.double(x)

y_matlab = matlab.double(y)

# Define the fitting function

fit_func = matlab.inline('a * sin(b * x)', 'x', 'a', 'b')

# Call lsqcurvefit in MATLAB

params = matlab.lsqcurvefit(fit_func, matlab.double([1, 1]), x_matlab, y_matlab)

# Extract the optimized parameters

a_opt, b_opt = params[0], params[1]

# Print the optimized parameters

print("Optimized parameters:")

print("a =", a_opt)

print("b =", b_opt)

# Stop MATLAB engine

matlab.quit()

[Kautuk Raj]

The inline function is not recommended to be used, check here.

Answer 1

[Hitesh]

Hi Kelly,

The "inline" function is not recommended by MATLAB documentation. You need to use the "eval" function to accomplish the same functionality. I have updated your code, and it executed successfully. Please see the revised version below in the below image:

For more information related to "eval" fucntion, kindly refer to the following MATLAB documentation:

https://www.mathworks.com/help/matlab/ref/eval.html