summaryrefslogtreecommitdiffstats
path: root/Doc/libmpz.tex
diff options
context:
space:
mode:
authorGuido van Rossum <guido@python.org>1994-01-02 01:22:07 (GMT)
committerGuido van Rossum <guido@python.org>1994-01-02 01:22:07 (GMT)
commit5fdeeeae2a12b9956cc84d62eae82f72cabc8664 (patch)
treeac0053479e10099850c8e0d06e31cb3afbf632bb /Doc/libmpz.tex
parent0b0719866e8a32d0a787e73bca9e79df1d1a74f8 (diff)
downloadcpython-5fdeeeae2a12b9956cc84d62eae82f72cabc8664.zip
cpython-5fdeeeae2a12b9956cc84d62eae82f72cabc8664.tar.gz
cpython-5fdeeeae2a12b9956cc84d62eae82f72cabc8664.tar.bz2
Restructured library documentation
Diffstat (limited to 'Doc/libmpz.tex')
-rw-r--r--Doc/libmpz.tex74
1 files changed, 74 insertions, 0 deletions
diff --git a/Doc/libmpz.tex b/Doc/libmpz.tex
new file mode 100644
index 0000000..ea0d1b7
--- /dev/null
+++ b/Doc/libmpz.tex
@@ -0,0 +1,74 @@
+\section{Built-in module \sectcode{mpz}}
+\bimodindex{mpz}
+
+This module implements the interface to part of the GNU MP library.
+This library contains arbitrary precision integer and rational number
+arithmetic routines. Only the interfaces to the \emph{integer}
+(\samp{mpz_{\rm \ldots}}) routines are provided. If not stated
+otherwise, the description in the GNU MP documentation can be applied.
+
+In general, \dfn{mpz}-numbers can be used just like other standard
+Python numbers, e.g. you can use the built-in operators like \code{+},
+\code{*}, etc., as well as the standard built-in functions like
+\code{abs}, \code{int}, \ldots, \code{divmod}, \code{pow}.
+\strong{Please note:} the {\it bitwise-xor} operation has been implemented as
+a bunch of {\it and}s, {\it invert}s and {\it or}s, because the library
+lacks an \code{mpz_xor} function, and I didn't need one.
+
+You create an mpz-number, by calling the function called \code{mpz} (see
+below for an excact description). An mpz-number is printed like this:
+\code{mpz(\var{value})}.
+
+\renewcommand{\indexsubitem}{(in module mpz)}
+\begin{funcdesc}{mpz}{value}
+ Create a new mpz-number. \var{value} can be an integer, a long,
+ another mpz-number, or even a string. If it is a string, it is
+ interpreted as an array of radix-256 digits, least significant digit
+ first, resulting in a positive number. See also the \code{binary}
+ method, described below.
+\end{funcdesc}
+
+A number of {\em extra} functions are defined in this module. Non
+mpz-arguments are converted to mpz-values first, and the functions
+return mpz-numbers.
+
+\begin{funcdesc}{powm}{base\, exponent\, modulus}
+ Return \code{pow(\var{base}, \var{exponent}) \%{} \var{modulus}}. If
+ \code{\var{exponent} == 0}, return \code{mpz(1)}. In contrast to the
+ \C-library function, this version can handle negative exponents.
+\end{funcdesc}
+
+\begin{funcdesc}{gcd}{op1\, op2}
+ Return the greatest common divisor of \var{op1} and \var{op2}.
+\end{funcdesc}
+
+\begin{funcdesc}{gcdext}{a\, b}
+ Return a tuple \code{(\var{g}, \var{s}, \var{t})}, such that
+ \code{\var{a}*\var{s} + \var{b}*\var{t} == \var{g} == gcd(\var{a}, \var{b})}.
+\end{funcdesc}
+
+\begin{funcdesc}{sqrt}{op}
+ Return the square root of \var{op}. The result is rounded towards zero.
+\end{funcdesc}
+
+\begin{funcdesc}{sqrtrem}{op}
+ Return a tuple \code{(\var{root}, \var{remainder})}, such that
+ \code{\var{root}*\var{root} + \var{remainder} == \var{op}}.
+\end{funcdesc}
+
+\begin{funcdesc}{divm}{numerator\, denominator\, modulus}
+ Returns a number \var{q}. such that
+ \code{\var{q} * \var{denominator} \%{} \var{modulus} == \var{numerator}}.
+ One could also implement this function in python, using \code{gcdext}.
+\end{funcdesc}
+
+An mpz-number has one method:
+
+\renewcommand{\indexsubitem}{(mpz method)}
+\begin{funcdesc}{binary}{}
+ Convert this mpz-number to a binary string, where the number has been
+ stored as an array of radix-256 digits, least significant digit first.
+
+ The mpz-number must have a value greater than- or equal to zero,
+ otherwise a \code{ValueError}-exception will be raised.
+\end{funcdesc}