# 5.1 Built-in Module math

This module is always available. It provides access to the mathematical functions defined by the C standard. They are:

acos (x)
Return the arc cosine of x.

asin (x)
Return the arc sine of x.

atan (x)
Return the arc tangent of x.

atan2 (x, y)
Return atan(x / y).

ceil (x)
Return the ceiling of x as a real.

cos (x)
Return the cosine of x.

cosh (x)
Return the hyperbolic cosine of x.

exp (x)
Return e**x.

fabs (x)
Return the absolute value of the real x.

floor (x)
Return the floor of x as a real.

fmod (x, y)
Return x % y.

frexp (x)
Return the matissa and exponent for x. The mantissa is positive.

hypot (x, y)
Return the Euclidean distance, sqrt(x*x + y*y).

ldexp (x, i)
Return x * (2**i).

log (x)
Return the natural logarithm of x.

log10 (x)
Return the base-10 logarithm of x.

modf (x)
Return the fractional and integer parts of x. Both results carry the sign of x. The integer part is returned as a real.

pow (x, y)
Return x**y.

sin (x)
Return the sine of x.

sinh (x)
Return the hyperbolic sine of x.

sqrt (x)
Return the square root of x.

tan (x)
Return the tangent of x.

tanh (x)
Return the hyperbolic tangent of x.

Note that frexp() and modf() have a different call/return pattern than their C equivalents: they take a single argument and return a pair of values, rather than returning their second return value through an `output parameter' (there is no such thing in Python).

The module also defines two mathematical constants:

pi
The mathematical constant pi.

e
The mathematical constant e.