# Python complex() Function with Examples

The complex() built-in python function is used to convert string into complex number or when a real and imaginary parts (i.e., 3+7j) are provided....

In this tutorial we will discuss about the complex() function in python programming language with the help of examples.

## Python complex() function

The built-in python function is used to convert string into complex number or when a real and imaginary parts (i.e., 3+7j) are provided it returns a complex number. The string passed to complex() function should be in form.

### Syntax

complex([real[, imag]])

## Parameters of complex() function in python

The complex() function in python takes two parameters;

- numeric type real part. 0 is to be the default value, if real part is omitted.

- numeric type imaginary part. 0 is to be the default value, if imag part is omitted.

## Return value of Python complex() function

In python, when a real and imaginary parts are provided function returns a complex number. It is also used to convert string into complex number. The string passed to complex() function should be in form.

Note - If the passed string is not a valid complex number then it will raise a [ValueError] exception.

#### Example 1: Creating a complex number in Python

x = complex(7, -2)

print(x)

x = complex(5)

print(x)

x = complex()

print(x)

x = complex('6-8j')

print(x)

Output

(7-2j)

(5+0j)

0j

(6-8j)

#### Example 2: Creating complex Number Without Using Python complex() function

a = 5+8j

print('a =',a)

print('Type of a is',type(a))

b = -3j

print('b =',b)

print('Type of b is',type(a))

c = 0j

print('c =',c)

print('Type of c is',type(c))

Output

a = (5+8j)

Type of a is <class 'complex'>

b = (-0-3j)

Type of b is <class 'complex'>

c = 0j

Type of c is <class 'complex'>

#### Example 3: The strings to be used as parameters in python complex() Function

x = complex('5'

y = complex('1.7')

print(x)

print(y)

Output

(5+0j)

(1.7+0j)

#### Example 4: The Python complex() function accepts only one string parameter as the input

x = complex('7','4')
print(x)

Output

TypeError: complex() can't take the second arg if first is a string