Python program to find the square root

By Lenin Mishra

Square root of Positive Numbers

Code

num = 4

sqrt_num = num ** 0.5
print(f"Square root of {num} is {sqrt_num}")

Output

Square root of 4 is 2.0

Square root of Positive numbers - through User Input

Code

num = input("Enter a number: ")

sqrt_num = float(num) ** 0.5
print(f"Square root of {num} is {sqrt_num}")

Output

Enter a number: 9
Square root of 9 is 3.0

Now be careful with this method. We are using the input() built in function of Python. Since it returns a string, we convert the string into number using the float() function. Then, the square root is calculated.

Using the built in int() function will chop off the decimal places.

Square root of Complex Numbers

Code

import cmath

num = 3+5j

sqrt_num = cmath.sqrt(num)
print(f"Square root of {num} is {sqrt_num}")

Output

Square root of (3+5j) is (2.101303392521568+1.189737764140758j)

Square root of Complex Numbers - through user input

Code

import cmath

user_input = input("Enter a complex number: ")
num = eval(user_input)

sqrt_num = cmath.sqrt(num)
print(f"Square root of {num} is {sqrt_num}")

Here we are using the eval() built in function in Python instead of float() to convert user input string to complex numbers.

Output

Enter a complex number: 2+3j
Square root of (2+3j) is (1.6741492280355401+0.8959774761298381j)

All the above codes use f-strings. Learn about python f-strings here.