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 0.0:

>>> 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

A 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)

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