Learn the numpy roots() function with code examples

The numpy roots() function is used to find the roots of a polynomial equation using the coefficient values.

The syntax of the function is as follows:

numpy.roots([n])

The roots accept an array of polynomial coefficients as [n, n, ...] and return the roots of the equation.

If the array length is n+1 then the polynomial is described by:

p[0] * x**n + p[1] * x**(n-1) + ... + p[n-1]*x + p[n]

For example, if you have the following equation: x2 - 5x + 6

The coefficients are 1, -5, and 6.

Use the root() function to solve find the roots:

import numpy as np

np.roots([1, -5, 6])

# array([3., 2.])

So x = 3, 2

You can also pass a floating number as one of the coefficient values:

import numpy as np

coeff = [3.7, 2, 1]

np.roots(coeff)

The output will be:

array([-0.27027027+0.44409937j, -0.27027027-0.44409937j])

And that’s how the numpy.roots() function works.