Calculate The Determinant Of A Matrix

h1ros

Goal¶

This post aims to show how to calculate the determinant of a matrix using numpy i.e., $|A|$

For example, if we have

$$A = \begin{bmatrix} a & b \\ c & d \end{bmatrix} $$

Then, $|A|$ is defined as

$$|A| = \begin{vmatrix} a & b \\ c & d \end{vmatrix} = ab - bc $$

Reference:

In [3]:

import numpy as np

In [6]:

a = np.array([[1,2], [3,4]]) 
a

Out[6]:

array([[1, 2],
       [3, 4]])

In [7]:

print(np.linalg.det(a))

-2.0000000000000004

In [8]:

a[0, 0] * a[1, 1] - a[0, 1] * a[1, 0]

Out[8]:

-2