\section{Built-in Module \sectcode{math}} \bimodindex{math} \renewcommand{\indexsubitem}{(in module math)} This module is always available. It provides access to the mathematical functions defined by the C standard. They are: \iftexi \begin{funcdesc}{acos}{x} \funcline{asin}{x} \funcline{atan}{x} \funcline{atan2}{x, y} \funcline{ceil}{x} \funcline{cos}{x} \funcline{cosh}{x} \funcline{exp}{x} \funcline{fabs}{x} \funcline{floor}{x} \funcline{fmod}{x, y} \funcline{frexp}{x} \funcline{hypot}{x, y} \funcline{ldexp}{x, y} \funcline{log}{x} \funcline{log10}{x} \funcline{modf}{x} \funcline{pow}{x, y} \funcline{sin}{x} \funcline{sinh}{x} \funcline{sqrt}{x} \funcline{tan}{x} \funcline{tanh}{x} \end{funcdesc} \else \code{acos(\varvars{x})}, \code{asin(\varvars{x})}, \code{atan(\varvars{x})}, \code{atan2(\varvars{x\, y})}, \code{ceil(\varvars{x})}, \code{cos(\varvars{x})}, \code{cosh(\varvars{x})}, \code{exp(\varvars{x})}, \code{fabs(\varvars{x})}, \code{floor(\varvars{x})}, \code{fmod(\varvars{x\, y})}, \code{frexp(\varvars{x})}, \code{ldexp(\varvars{x\, y})}, \code{log(\varvars{x})}, \code{log10(\varvars{x})}, \code{modf(\varvars{x})}, \code{pow(\varvars{x\, y})}, \code{sin(\varvars{x})}, \code{sinh(\varvars{x})}, \code{sqrt(\varvars{x})}, \code{tan(\varvars{x})}, \code{tanh(\varvars{x})}. \fi Note that \code{frexp} and \code{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: \iftexi \begin{datadesc}{pi} \dataline{e} \end{datadesc} \else \code{pi} and \code{e}. \fi