Python in a Nutshell, 2nd Edition

The math and cmath Modules

The math module supplies mathematical functions on floating-point numbers, while the cmath module supplies equivalent functions on complex numbers. For example, math.sqrt(-1) raises an exception, but cmath.sqrt(-1) returns 1j.

Each module exposes two attributes of type float bound to the values of fundamental mathematical constants, pi and e, and the following functions.

acos	acos(x) Returns the arccosine of x in radians.	math and cmath
acosh	acosh(x) Returns the arc hyperbolic cosine of x in radians.	cmath only
asin	asin(x) Returns the arcsine of x in radians.	math and cmath
asinh	asinh(x) Returns the arc hyperbolic sine of x in radians.	cmath only
atan	atan(x) Returns the arctangent of x in radians.	math and cmath
atanh	atanh(x) Returns the arc hyperbolic tangent of x in radians.	cmath only
atan2	atan2(y,x) Like atan(y/x), except that atan2 properly takes into account the signs of both arguments. For example: >>> import math >>> math.atan(-1./-1.) 0.78539816339744828 >>> math.atan2(-1., -1.) -2.3561944901923448 Also, when x equals 0, atan2 returns pi/2, while dividing by x would raise ZeroDivisionError.	math only
ceil	ceil(x) Returns float(i), where i is the lowest integer such that i >= x.	math only
cos	cos(x) Returns the cosine of x in radians.	math and cmath
cosh	cosh(x) Returns the hyperbolic cosine of x in radians.	math and cmath
e	The mathematical constant e.	math and cmath
exp	exp(x) Returns e**x.	math and cmath
fabs	fabs(x) Returns the absolute value of x.	math only
floor	floor(x)