# Python Program to Find the Square Root

In this program, you'll learn to find the square root of a number using exponent operator and cmath module.

To understand this example, you should have the knowledge of following Python programming topics:

## Source Code: For positive numbers using exponent **

```# Python Program to calculate the square root

# Note: change this value for a different result
num = 8

# uncomment to take the input from the user
#num = float(input('Enter a number: '))
num_sqrt = num ** 0.5
print('The square root of %0.3f is %0.3f'%(num ,num_sqrt))
```

Output

```The square root of 8.000 is 2.828
```

In this program, we store the number in num and find the square root using the `**` exponent operator. This program works for all positive real numbers. But for negative or complex numbers, it can be done as follows.

## Source code: For real or complex numbers using cmath module

```# Find square root of real or complex numbers
# Import the complex math module
import cmath

# change this value for a different result
num = 1+2j

# uncommment to take input from the user
#num = eval(input('Enter a number: '))
num_sqrt = cmath.sqrt(num)
print('The square root of {0} is {1:0.3f}+{2:0.3f}j'.format(num ,num_sqrt.real,num_sqrt.imag))
```

Output

`The square root of (1+2j) is 1.272+0.786j`

In this program, we use the `sqrt()` function in the cmath (complex math) module.

Notice that we have used the `eval()` function instead of `float()` to convert complex number as well. Also notice the way in which the output is formatted.

Look here for more about string formatting in Python.