Complex numbers are an extension of the familiar real number system in which all numbers are expressed as a sum of a real part and an imaginary part. Imaginary numbers are real multiples of the imaginary unit (the square root of -1), often written i in mathematics or j in engineering. Python has built-in support for complex numbers, which are written with this latter notation; the imaginary part is written with a j suffix, e.g., 3+1j. To get access to complex equivalents of the math module, use cmath. Use of complex numbers is a fairly advanced mathematical feature. If you’re not aware of a need for them, it’s almost certain you can safely ignore them.

Complex numbers are stored as a pair of machine-level double precision floating point numbers.


Returns an expression converted into a complex number.
literal syntax
Initializes a new instance of the complex type.


Retrieves the real component of this number.
Retrieves the imaginary component of this number.


Returns the complex conjugate.