Parse a matrix in a textfile into an actual (array-based) matrix in python?

Question

I am trying to parse a textfile where a matrix is saved in the string format: "[[0,1],[1,0]]"

To goal is to parse the .txt file and turn it into an actual matrix represented by an arrays of arrays stored in some variable. I am new to python and programming in general and can't think of an nice way to do this.

I only need help with how to construct the python matrix from what we get in the .txt file.

As stated in the above link, `eval("[[0,1],[1,0]]")` is the solution. — Kraigolas, Feb 27 '21 at 16:41

score 0 · Accepted Answer · answered Feb 27 '21 at 17:02

As commented by @Kraigolas, the python eval() function will evaluate that expression and convert it to a Python list of lists.

To elaborate further, if you want to then work with it as a matrix, your best bet is to then convert it to a NumPy array.

This can be a one liner:

import numpy as np
arr = np.array(eval("[[0,1],[1,0]]"))

You then can work with arr using NumPy as you wish.

Parse a matrix in a textfile into an actual (array-based) matrix in python?

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