AttributeError: module 'numpy' has no attribute 'matlib'

This error occurs when you try to use the matlib module in NumPy, but NumPy does not recognize it. The matlib module is a sub-module of NumPy that provides a matrix library that is similar to MATLAB's matrix library.

To fix this error, you can try importing the matlib module explicitly by adding the following line of code at the beginning of your script:

import numpy.matlib

Then, you can use the matlib module as follows:

import numpy as np

matrix = np.matlib.ones((3, 3))
print(matrix)

This will create a 3x3 matrix of ones using the matlib module in NumPy.