title: Python Complex Numbers
Complex numbers have a real and an imaginary part, each represented by a floating point number.
The imaginary part of a complex number can be created using an imaginary literal, this results in a complex number with a real part of
>>> a = 3.5j >>> type(a) <class 'complex'> >>> print(a) 3.5j >>> a.real 0.0 >>> a.imag 3.5
No literal exists for creating a complex number with non-zero real and imaginary parts. To create a non-zero real part complex number, add an imaginary literal to a floating point number:
>>> a = 1.1 + 3.5j >>> type(a) <class 'complex'> >>> print(a) (1.1+3.5j) >>> a.real 1.1 >>> a.imag 3.5
Or use the complex constructor.
class complex([real[, imag]])
The arguments used to call the complex constructor can be of numeric (including
complex) type for either parameter:
>>> complex(1, 1) (1+1j) >>> complex(1j, 1j) (-1+1j) >>> complex(1.1, 3.5) (1.1+3.5j) >>> complex(1.1) (1.1+0j) >>> complex(0, 3.5) 3.5j
string can also be used as the argument. No second argument is allowed if a string is used as an argument
>>> complex("1.1+3.5j") (1.1+3.5j)
We can obtain the absolute value of a complex number using the abs() method in python.
>>> a=2+3j >>> abs(a) 3.605551275463989 >>> b=-1+1j >>> abs(b) 1.4142135623730951