Python - math.sqrt() method example

math.sqrt is a method that returns a number which is the square root of input value. The method works only on positive real numbers.

import math

print( math.sqrt(  4   ) ) # 2
print( math.sqrt(  9   ) ) # 3

print( math.sqrt(  2   ) ) # 1.4142135623730951
print( math.sqrt(  0.5 ) ) # 0.7071067811865476
print( math.sqrt(  0   ) ) # 0
print( math.sqrt( -1   ) ) # ValueError

1. Documentation

math.sqrt(x)

2. Square root with math.pow method examples

In this example, the way how to calculate square root using power function is presented. 

import math


def calculate_sqrt(value):
    return math.pow(value, 0.5)


#Examples:
print( calculate_sqrt(  4   ) ) # 2
print( calculate_sqrt(  9   ) ) # 3

print( calculate_sqrt(  2   ) ) # 1.4142135623730951
print( calculate_sqrt(  0.5 ) ) # 0.7071067811865476
print( calculate_sqrt(  0   ) ) # 0
print( calculate_sqrt( -1   ) ) # ValueError