# # Mathematical functions with automatic domain (numpy.emath)

Note

numpy.emath is a preferred alias for numpy.lib.scimath, available after numpy is imported.

Wrapper functions to more user-friendly calling of certain math functions whose output data-type is different than the input data-type in certain domains of the input.

For example, for functions like log with branch cuts, the versions in this module provide the mathematically valid answers in the complex plane:

>>> import math
>>> from numpy.lib import scimath
>>> scimath.log(-math.exp(1)) == (1+1j*math.pi)
True


Similarly, sqrt, other base logarithms, power and trig functions are correctly handled. See their respective docstrings for specific examples.