Built-in Functions

The Python interpreter has a number of functions built into it that are always available. They are listed here in alphabetical order.

$\begin{funcdesc}{abs}{x} Return the absolute value of a number. The argument may be a plain or long integer or a floating point number. \end{funcdesc}$

$\begin{funcdesc}{apply}{function\, args} The \var{function} argument must be a c... ...rgs})}, since in that case there is always exactly one argument.) \end{funcdesc}$

$\begin{funcdesc}{chr}{i} Return a string of one character whose \ASCII{} code i... ...e{ord()}. The argument must be in the range [0..255], inclusive. \end{funcdesc}$

$\begin{funcdesc}{cmp}{x\, y} Compare the two objects \var{x} and \var{y} and re... ...} == \var{y}} and strictly positive if \code{\var{x} > \var{y}}. \end{funcdesc}$

$\begin{funcdesc}{coerce}{x\, y} Return a tuple consisting of the two numeric ar... ...mon type, using the same rules as used by arithmetic operations. \end{funcdesc}$

$\begin{funcdesc}{compile}{string\, filename\, kind} Compile the \var{string} in... ...tements, or \code{'eval'} if it consists of a single expression. \end{funcdesc}$

$\begin{funcdesc}{dir}{} Without arguments, return the list of names in the curr... ...es', 'path', 'stderr', 'stdin', 'stdout'] >>>\end{verbatim}\ecode \end{funcdesc}$

$\begin{funcdesc}{divmod}{a\, b} Take two numbers as arguments and return a pair... ...as \code{(math.floor(\var{a} / \var{b}), \var{a} \%{} \var{b})}. \end{funcdesc}$

$\begin{funcdesc}{eval}{s\, globals\, locals} The arguments are a string and two... ...on of statements is supported by the \code{exec} statement. \par \end{funcdesc}$

$\begin{funcdesc}{filter}{function\, list} Construct a list from those elements o... ...lements of \var{list} that are false (zero or empty) are removed. \end{funcdesc}$

$\begin{funcdesc}{float}{x} Convert a number to floating point. The argument may be a plain or long integer or a floating point number. \end{funcdesc}$

$\begin{funcdesc}{getattr}{object\, name} The arguments are an object and a stri... ..., '\var{foobar}')} is equivalent to \code{\var{x}.\var{foobar}}. \end{funcdesc}$

$\begin{funcdesc}{hasattr}{object\, name} The arguments are an object and a stri... ...bject, name)} and seeing whether it raises an exception or not.) \end{funcdesc}$

$\begin{funcdesc}{hash}{object} Return the hash value of the object (if it has o... ...ash value (even if they are of different types, e.g. 1 and 1.0). \end{funcdesc}$

$\begin{funcdesc}{hex}{x} Convert a number to a hexadecimal string. The result is a valid Python expression. \end{funcdesc}$

$\begin{funcdesc}{id}{object} Return the \lq identity' of an object. This is an int... ...alue.) (Implementation note: this is the address of the object.) \end{funcdesc}$

$\begin{funcdesc}{input}{prompt} Almost equivalent to \code{eval(raw_input(\var{... ...ay be broken over multiple lines using the backslash convention. \end{funcdesc}$

$\begin{funcdesc}{int}{x} Convert a number to a plain integer. The argument may be a plain or long integer or a floating point number. \end{funcdesc}$

$\begin{funcdesc}{len}{s} Return the length (the number of items) of an object. ... ... be a sequence (string, tuple or list) or a mapping (dictionary). \end{funcdesc}$

$\begin{funcdesc}{long}{x} Convert a number to a long integer. The argument may be a plain or long integer or a floating point number. \end{funcdesc}$

$\begin{funcdesc}{map}{function\, list\, ...} Apply \var{function} to every item ... ...guments may be any kind of sequence; the result is always a list. \end{funcdesc}$

$\begin{funcdesc}{max}{s} Return the largest item of a non-empty sequence (string, tuple or list). \end{funcdesc}$

$\begin{funcdesc}{min}{s} Return the smallest item of a non-empty sequence (string, tuple or list). \end{funcdesc}$

$\begin{funcdesc}{oct}{x} Convert a number to an octal string. The result is a valid Python expression. \end{funcdesc}$

$\begin{funcdesc}{open}{filename\, mode\, bufsize} Return a new file object (des... ...r tty devices and fully buffered for other files.% \footnotemark \end{funcdesc}$

$\begin{funcdesc}{ord}{c} Return the \ASCII{} value of a string of one character... ...urns the integer \code{97}. This is the inverse of \code{chr()}. \end{funcdesc}$

$\begin{funcdesc}{pow}{x\, y} Return \var{x} to the power \var{y}. The arguments... ...tion raises an exception; e.g., \code{pow(2, -1)} is not allowed. \end{funcdesc}$

$\begin{funcdesc}{range}{start\, end\, step} This is a versatile function to cre... ...8, -9] >>> range(0) [] >>> range(1, 0) [] >>>\end{verbatim}\ecode \end{funcdesc}$

$\begin{funcdesc}{raw_input}{prompt} The string argument is optional; if present... ...cus >>> s 'Monty Python\'s Flying Circus' >>>\end{verbatim}\ecode \end{funcdesc}$

$\begin{funcdesc}{reduce}{function\, list\, initializer} Apply the binary \var{fu... ...\var{list}. The \var{list} arguments may be any kind of sequence. \end{funcdesc}$

$\begin{funcdesc}{reload}{module} Re-parse and re-initialize an already imported... ...ized module object available) before you can \code{reload()} it. \end{funcdesc}$

$\begin{funcdesc}{repr}{object} Return a string containing a printable representa... ...yield an object with the same value when passed to \code{eval()}. \end{funcdesc}$

$\begin{funcdesc}{round}{x\, n} Return the floating point value \var{x} rounded ... ...round(0.5)} is \code{1.0} and \code{round(-0.5)} is \code{-1.0}). \end{funcdesc}$

$\begin{funcdesc}{setattr}{object\, name\, value} This is the counterpart of \co... ...bar}', 123)} is equivalent to \code{\var{x}.\var{foobar} = 123}. \end{funcdesc}$

$\begin{funcdesc}{str}{object} Return a string containing a nicely printable repr... ...table to \code{eval()}; its goal is to return a printable string. \end{funcdesc}$

$\begin{funcdesc}{type}{object} Return the type of an \var{object}. The return va... ...f type(x) == type(''): print 'It is a string'\end{verbatim}\ecode \end{funcdesc}$

$\begin{funcdesc}{vars}{} Without arguments, return a dictionary corresponding to... ... on the corresponding symbol table are undefined.% \footnotemark \end{funcdesc}$

$\begin{funcdesc}{xrange}{start\, end\, step} This function is very similar to \c... ...sed (e.g. when the loop is usually terminated with \code{break}). \end{funcdesc}$