Python: complex() function

complex() function

The complex() function is used to create a complex number or convert a string or number to a complex number.

The complex type is described in Numeric Types — int, float, complex.


complex([real[, imag]])
Python: Built-in function - complex function()


(Python 3)

If the first parameter is a string, it will be interpreted as a complex number and the function must be called without a second parameter.

The second parameter can never be a string. Each argument may be any numeric type (including complex).

If imag is omitted, it defaults to zero and the function serves as a numeric conversion function like int() and float(). If both arguments are omitted, returns 0j.

Return value:

Return a complex number with the value real + imag*1j or convert a string or number to a complex number.

Note: When converting from a string, the string must not contain whitespace around the central + or - operator. For example, complex('1+2j') is fine, but complex('1 + 2j') raises ValueError.

Example: Create a complex number in Python

x = complex(3, -5)
x = complex(1)
x = complex()
x = complex('6-7j')



Pictorial Presentation:

Python: Built-in-function - complex() function

Pictorial Presentation:

Python: Built-in-function - complex() function

Example: Create complex Number Without Using complex()

x = 3+5j
print('x =',x)
print('Type of x is',type(x))

y = -5j
print('y =',y)
print('Type of y is',type(x))

z = 0j
print('z =',z)
print('Type of z is',type(z))


x = (3+5j)
Type of x is 
y = (-0-5j)
Type of y is 
z = 0j
Type of z is 

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