matrix - How to "join" sub-matrices to create larger matrices on Python?

Question

For $m < n$ suppose I have sampled a $m imes m$ random matrix and a $m imes (n-m)$ random matrix. I want to be able to join the later to the right of the former and create a $m imes n$ random matrix.

• Can someone kindly suggest a way to achieve this?

question from:https://stackoverflow.com/questions/65850975/how-to-join-sub-matrices-to-create-larger-matrices-on-python

Answer 1

Solution with numpy arrays:

import numpy
# assuming m2 and m1 are already created
m3 = numpy.concatenate((m2, m1), axis=1)

With m2 being m x m, and m1 being m x (n-m).

For 2d matrices, axis=0 concatenates them vertically, axis=1 concatenates them horizontally.

You could also look into numpy.hstack().

Read the docs, they tell you exactly what these functions do and how to use them.