\bifuncindex{float}
\bifuncindex{complex}
-All numeric types support the following operations, sorted by
-ascending priority (operations in the same box have the same
+All numeric types (except complex) support the following operations,
+sorted by ascending priority (operations in the same box have the same
priority; all numeric operations have a higher priority than
comparison operations):
\hline
\lineiii{\var{x} * \var{y}}{product of \var{x} and \var{y}}{}
\lineiii{\var{x} / \var{y}}{quotient of \var{x} and \var{y}}{(1)}
- \lineiii{\var{x} \%{} \var{y}}{remainder of \code{\var{x} / \var{y}}}{}
+ \lineiii{\var{x} \%{} \var{y}}{remainder of \code{\var{x} / \var{y}}}{(4)}
\hline
\lineiii{-\var{x}}{\var{x} negated}{}
\lineiii{+\var{x}}{\var{x} unchanged}{}
\lineiii{float(\var{x})}{\var{x} converted to floating point}{}
\lineiii{complex(\var{re},\var{im})}{a complex number with real part \var{re}, imaginary part \var{im}. \var{im} defaults to zero.}{}
\lineiii{\var{c}.conjugate()}{conjugate of the complex number \var{c}}{}
- \lineiii{divmod(\var{x}, \var{y})}{the pair \code{(\var{x} / \var{y}, \var{x} \%{} \var{y})}}{(3)}
+ \lineiii{divmod(\var{x}, \var{y})}{the pair \code{(\var{x} / \var{y}, \var{x} \%{} \var{y})}}{(3)(4)}
\lineiii{pow(\var{x}, \var{y})}{\var{x} to the power \var{y}}{}
\lineiii{\var{x} ** \var{y}}{\var{x} to the power \var{y}}{}
\end{tableiii}
See section \ref{built-in-funcs}, ``Built-in Functions,'' for a full
description.
+\item[(4)]
+Complex floor division operator, modulo operator, and \function{divmod()}.
+
+\deprecated{2.3}{Instead convert to float using \function{abs()}
+if appropriate.}
+
\end{description}
% XXXJH exceptions: overflow (when? what operations?) zerodivision
\hline
\lineiii{\var{s}[\var{i}]}{\var{i}'th item of \var{s}, origin 0}{(3)}
\lineiii{\var{s}[\var{i}:\var{j}]}{slice of \var{s} from \var{i} to \var{j}}{(3), (4)}
+ \lineiii{\var{s}[\var{i}:\var{j}:\var{k}]}{slice of \var{s} from \var{i} to \var{j} with step \var{k}}{(3), (5)}
\hline
\lineiii{len(\var{s})}{length of \var{s}}{}
\lineiii{min(\var{s})}{smallest item of \var{s}}{}
\indexii{repetition}{operation}
\indexii{subscript}{operation}
\indexii{slice}{operation}
+\indexii{extended slice}{operation}
\opindex{in}
\opindex{not in}
\code{len(\var{s})}, use \code{len(\var{s})}. If \var{i} is omitted,
use \code{0}. If \var{j} is omitted, use \code{len(\var{s})}. If
\var{i} is greater than or equal to \var{j}, the slice is empty.
+
+\item[(5)] The slice of \var{s} from \var{i} to \var{j} with step
+ \var{k} is defined as the sequence of items with index
+ \code{\var{x} = \var{i} + \var{n}*\var{k}} such that \code{0}
+ \code{<=} \var{n} \code{<} \code{abs(i-j)}. If \var{i} or \var{j}
+ is greater than \code{len(\var{s})}, use \code{len(\var{s})}. If
+ \var{i} or \var{j} are ommitted then they become ``end'' values
+ (which end depends on the sign of \var{k}).
+
\end{description}
\end{methoddesc}
\begin{methoddesc}[string]{endswith}{suffix\optional{, start\optional{, end}}}
-Return true if the string ends with the specified \var{suffix},
-otherwise return false. With optional \var{start}, test beginning at
+Return \code{True} if the string ends with the specified \var{suffix},
+otherwise return \code{False}. With optional \var{start}, test beginning at
that position. With optional \var{end}, stop comparing at that position.
\end{methoddesc}
\begin{methoddesc}[string]{startswith}{prefix\optional{,
start\optional{, end}}}
-Return true if string starts with the \var{prefix}, otherwise
-return false. With optional \var{start}, test string beginning at
+Return \code{True} if string starts with the \var{prefix}, otherwise
+return \code{False}. With optional \var{start}, test string beginning at
that position. With optional \var{end}, stop comparing string at that
position.
\end{methoddesc}
{slice of \var{s} from \var{i} to \var{j} is replaced by \var{t}}{}
\lineiii{del \var{s}[\var{i}:\var{j}]}
{same as \code{\var{s}[\var{i}:\var{j}] = []}}{}
+ \lineiii{\var{s}[\var{i}:\var{j}:\var{k}] = \var{t}}
+ {the elements of \code{\var{s}[\var{i}:\var{j}:\var{k}]} are replaced by those of \var{t}}{(1)}
+ \lineiii{del \var{s}[\var{i}:\var{j}:\var{k}]}
+ {removes the elements of \code{\var{s}[\var{i}:\var{j}:\var{k}]} from the list}{}
\lineiii{\var{s}.append(\var{x})}
- {same as \code{\var{s}[len(\var{s}):len(\var{s})] = [\var{x}]}}{(1)}
+ {same as \code{\var{s}[len(\var{s}):len(\var{s})] = [\var{x}]}}{(2)}
\lineiii{\var{s}.extend(\var{x})}
- {same as \code{\var{s}[len(\var{s}):len(\var{s})] = \var{x}}}{(2)}
+ {same as \code{\var{s}[len(\var{s}):len(\var{s})] = \var{x}}}{(3)}
\lineiii{\var{s}.count(\var{x})}
{return number of \var{i}'s for which \code{\var{s}[\var{i}] == \var{x}}}{}
\lineiii{\var{s}.index(\var{x})}
- {return smallest \var{i} such that \code{\var{s}[\var{i}] == \var{x}}}{(3)}
+ {return smallest \var{i} such that \code{\var{s}[\var{i}] == \var{x}}}{(4)}
\lineiii{\var{s}.insert(\var{i}, \var{x})}
{same as \code{\var{s}[\var{i}:\var{i}] = [\var{x}]}
- if \code{\var{i} >= 0}}{(4)}
+ if \code{\var{i} >= 0}}{(5)}
\lineiii{\var{s}.pop(\optional{\var{i}})}
- {same as \code{\var{x} = \var{s}[\var{i}]; del \var{s}[\var{i}]; return \var{x}}}{(5)}
+ {same as \code{\var{x} = \var{s}[\var{i}]; del \var{s}[\var{i}]; return \var{x}}}{(6)}
\lineiii{\var{s}.remove(\var{x})}
- {same as \code{del \var{s}[\var{s}.index(\var{x})]}}{(3)}
+ {same as \code{del \var{s}[\var{s}.index(\var{x})]}}{(4)}
\lineiii{\var{s}.reverse()}
- {reverses the items of \var{s} in place}{(6)}
+ {reverses the items of \var{s} in place}{(7)}
\lineiii{\var{s}.sort(\optional{\var{cmpfunc=None}})}
- {sort the items of \var{s} in place}{(6), (7), (8), (9)}
+ {sort the items of \var{s} in place}{(7), (8), (9), (10)}
\end{tableiii}
\indexiv{operations on}{mutable}{sequence}{types}
\indexiii{operations on}{sequence}{types}
\indexiii{operations on}{list}{type}
\indexii{subscript}{assignment}
\indexii{slice}{assignment}
+\indexii{extended slice}{assignment}
\stindex{del}
\withsubitem{(list method)}{
\ttindex{append()}\ttindex{extend()}\ttindex{count()}\ttindex{index()}
\noindent
Notes:
\begin{description}
-\item[(1)] The C implementation of Python historically accepted
- multiple parameters and implicitly joined them into a tuple;
- Use of this misfeature has been deprecated since Python 1.4,
- and became an error with the introduction of Python 2.0.
+\item[(1)] \var{t} must have the same length as the slice it is
+ replacing.
-\item[(2)] Raises an exception when \var{x} is not an iterable object.
+\item[(2)] The C implementation of Python has historically accepted
+ multiple parameters and implicitly joined them into a tuple; this
+ no longer works in Python 2.0. Use of this misfeature has been
+ deprecated since Python 1.4.
-\item[(3)] Raises \exception{ValueError} when \var{x} is not found in
+\item[(3)] Raises an exception when \var{x} is not a list object. The
+ \method{extend()} method is experimental and not supported by
+ mutable sequence types other than lists.
+
+\item[(4)] Raises \exception{ValueError} when \var{x} is not found in
\var{s}.
-\item[(4)] When a negative index is passed as the first parameter to
+\item[(5)] When a negative index is passed as the first parameter to
the \method{insert()} method, the new element is prepended to the
sequence.
-\item[(5)] The \method{pop()} method is only supported by the list and
+\item[(6)] The \method{pop()} method is only supported by the list and
array types. The optional argument \var{i} defaults to \code{-1},
so that by default the last item is removed and returned.
-\item[(6)] The \method{sort()} and \method{reverse()} methods modify the
+\item[(7)] The \method{sort()} and \method{reverse()} methods modify the
list in place for economy of space when sorting or reversing a large
list. To remind you that they operate by side effect, they don't return
the sorted or reversed list.
-\item[(7)] The \method{sort()} method takes an optional argument
+\item[(8)] The \method{sort()} method takes an optional argument
specifying a comparison function of two arguments (list items) which
should return a negative, zero or positive number depending on whether
the first argument is considered smaller than, equal to, or larger
comparison function is semantically equivalent to calling
\method{sort()} with no comparison function.
-\item[(8)] Whether the \method{sort()} method is stable is not defined by
+\item[(9)] Whether the \method{sort()} method is stable is not defined by
the language (a sort is stable if it guarantees not to change the
relative order of elements that compare equal). In the C
implementation of Python, sorts were stable only by accident through
\method{sort()} method, but code that intends to be portable across
implementations and versions must not rely on stability.
-\item[(9)] While a list is being sorted, the effect of attempting to
+\item[(10)] While a list is being sorted, the effect of attempting to
mutate, or even inspect, the list is undefined. The C implementation
of Python 2.3 makes the list appear empty for the duration, and raises
\exception{ValueError} if it can detect that the list has been
\ttindex{keys()}
\ttindex{update()}
\ttindex{values()}
- \ttindex{get()}}
+ \ttindex{get()}
+ \ttindex{setdefault()}
+ \ttindex{pop()}
+ \ttindex{popitem()}
+ \ttindex{iteritems()}
+ \ttindex{iterkeys)}
+ \ttindex{itervalues()}}
\begin{tableiii}{c|l|c}{code}{Operation}{Result}{Notes}
\lineiii{len(\var{a})}{the number of items in \var{a}}{}
attribute and may not be present on all file-like objects.
\end{memberdesc}
+\begin{memberdesc}[file]{newlines}
+If Python was built with the \code{--with-universal-newlines} option
+(the default) this read-only attribute exists, and for files opened in
+universal newline read mode it keeps track of the types of newlines
+encountered while reading the file. The values it can take are
+\code{'\e r'}, \code{'\e n'}, \code{'\e r\e n'}, \code{None} (unknown,
+no newlines read yet) or a tuple containing all the newline
+types seen, to indicate that multiple
+newline conventions were encountered. For files not opened in universal
+newline read mode the value of this attribute will be \code{None}.
+\end{memberdesc}
+
\begin{memberdesc}[file]{softspace}
Boolean that indicates whether a space character needs to be printed
before another value when using the \keyword{print} statement.
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