53 lines
1.7 KiB
TeX
53 lines
1.7 KiB
TeX
\section{\module{whrandom} ---
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Floating point pseudo-random number generator.}
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\declaremodule{standard}{whrandom}
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\modulesynopsis{Floating point pseudo-random number generator.}
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This module implements a Wichmann-Hill pseudo-random number generator
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class that is also named \code{whrandom}. Instances of the
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\code{whrandom} class have the following methods:
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\begin{funcdesc}{choice}{seq}
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Chooses a random element from the non-empty sequence \var{seq} and returns it.
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\end{funcdesc}
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\begin{funcdesc}{randint}{a, b}
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Returns a random integer \var{N} such that \code{\var{a}<=\var{N}<=\var{b}}.
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\end{funcdesc}
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\begin{funcdesc}{random}{}
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Returns the next random floating point number in the range [0.0 ... 1.0).
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\end{funcdesc}
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\begin{funcdesc}{seed}{x, y, z}
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Initializes the random number generator from the integers
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\var{x},
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\var{y}
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and
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\var{z}.
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When the module is first imported, the random number is initialized
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using values derived from the current time.
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\end{funcdesc}
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\begin{funcdesc}{uniform}{a, b}
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Returns a random real number \var{N} such that \code{\var{a}<=\var{N}<\var{b}}.
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\end{funcdesc}
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When imported, the \code{whrandom} module also creates an instance of
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the \code{whrandom} class, and makes the methods of that instance
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available at the module level. Therefore one can write either
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\code{N = whrandom.random()} or:
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\begin{verbatim}
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generator = whrandom.whrandom()
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N = generator.random()
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\end{verbatim}
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%
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\begin{seealso}
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\seemodule{random}{generators for various random distributions}
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\seetext{Wichmann, B. A. \& Hill, I. D., ``Algorithm AS 183:
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An efficient and portable pseudo-random number generator'',
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\emph{Applied Statistics} 31 (1982) 188-190}
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\end{seealso}
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