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diff --git a/share/doc/gfortran/RANDOM_005fINIT.html b/share/doc/gfortran/RANDOM_005fINIT.html new file mode 100644 index 0000000..e6deef1 --- /dev/null +++ b/share/doc/gfortran/RANDOM_005fINIT.html @@ -0,0 +1,144 @@ +<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> +<html> +<!-- Copyright (C) 1999-2023 Free Software Foundation, Inc. + +Permission is granted to copy, distribute and/or modify this document +under the terms of the GNU Free Documentation License, Version 1.3 or +any later version published by the Free Software Foundation; with the +Invariant Sections being "Funding Free Software", the Front-Cover +Texts being (a) (see below), and with the Back-Cover Texts being (b) +(see below). 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Copies published by the Free Software Foundation raise + funds for GNU development. --> +<!-- Created by GNU Texinfo 5.1, http://www.gnu.org/software/texinfo/ --> +<head> +<title>The GNU Fortran Compiler: RANDOM_INIT</title> + +<meta name="description" content="The GNU Fortran Compiler: RANDOM_INIT"> +<meta name="keywords" content="The GNU Fortran Compiler: RANDOM_INIT"> +<meta name="resource-type" content="document"> +<meta name="distribution" content="global"> +<meta name="Generator" content="makeinfo"> +<meta http-equiv="Content-Type" content="text/html; charset=utf-8"> +<link href="index.html#Top" rel="start" title="Top"> +<link href="Option-Index.html#Option-Index" rel="index" title="Option Index"> +<link href="index.html#SEC_Contents" rel="contents" title="Table of Contents"> +<link href="Intrinsic-Procedures.html#Intrinsic-Procedures" rel="up" title="Intrinsic Procedures"> +<link href="RANDOM_005fNUMBER.html#RANDOM_005fNUMBER" rel="next" title="RANDOM_NUMBER"> +<link href="RAND.html#RAND" rel="previous" title="RAND"> +<style type="text/css"> +<!-- +a.summary-letter {text-decoration: none} +blockquote.smallquotation {font-size: smaller} +div.display {margin-left: 3.2em} +div.example {margin-left: 3.2em} +div.indentedblock {margin-left: 3.2em} +div.lisp {margin-left: 3.2em} +div.smalldisplay {margin-left: 3.2em} +div.smallexample {margin-left: 3.2em} +div.smallindentedblock {margin-left: 3.2em; font-size: smaller} +div.smalllisp {margin-left: 3.2em} +kbd {font-style:oblique} +pre.display {font-family: inherit} +pre.format {font-family: inherit} +pre.menu-comment {font-family: serif} +pre.menu-preformatted {font-family: serif} +pre.smalldisplay {font-family: inherit; font-size: smaller} +pre.smallexample {font-size: smaller} +pre.smallformat {font-family: inherit; font-size: smaller} +pre.smalllisp {font-size: smaller} +span.nocodebreak {white-space:nowrap} +span.nolinebreak {white-space:nowrap} +span.roman {font-family:serif; font-weight:normal} +span.sansserif {font-family:sans-serif; font-weight:normal} +ul.no-bullet {list-style: none} +--> +</style> + + +</head> + +<body lang="en" bgcolor="#FFFFFF" text="#000000" link="#0000FF" vlink="#800080" alink="#FF0000"> +<a name="RANDOM_005fINIT"></a> +<div class="header"> +<p> +Next: <a href="RANDOM_005fNUMBER.html#RANDOM_005fNUMBER" accesskey="n" rel="next">RANDOM_NUMBER</a>, Previous: <a href="RAND.html#RAND" accesskey="p" rel="previous">RAND</a>, Up: <a href="Intrinsic-Procedures.html#Intrinsic-Procedures" accesskey="u" rel="up">Intrinsic Procedures</a> [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Option-Index.html#Option-Index" title="Index" rel="index">Index</a>]</p> +</div> +<hr> +<a name="RANDOM_005fINIT-_002d_002d_002d-Initialize-a-pseudo_002drandom-number-generator"></a> +<h3 class="section">8.223 <code>RANDOM_INIT</code> — Initialize a pseudo-random number generator</h3> +<a name="index-RANDOM_005fINIT"></a> +<a name="index-random-number-generation_002c-initialization"></a> + +<dl compact="compact"> +<dt><em>Description</em>:</dt> +<dd><p>Initializes the state of the pseudorandom number generator used by +<code>RANDOM_NUMBER</code>. +</p> +</dd> +<dt><em>Standard</em>:</dt> +<dd><p>Fortran 2018 +</p> +</dd> +<dt><em>Class</em>:</dt> +<dd><p>Subroutine +</p> +</dd> +<dt><em>Syntax</em>:</dt> +<dd><p><code>CALL RANDOM_INIT(REPEATABLE, IMAGE_DISTINCT)</code> +</p> +</dd> +<dt><em>Arguments</em>:</dt> +<dd><table> +<tr><td width="25%"><var>REPEATABLE</var></td><td width="70%">Shall be a scalar with a <code>LOGICAL</code> type, +and it is <code>INTENT(IN)</code>. If it is <code>.true.</code>, the seed is set to +a processor-dependent value that is the same each time <code>RANDOM_INIT</code> +is called from the same image. The term “same image” means a single +instance of program execution. The sequence of random numbers is different +for repeated execution of the program. If it is <code>.false.</code>, the seed +is set to a processor-dependent value.</td></tr> +<tr><td width="25%"><var>IMAGE_DISTINCT</var></td><td width="70%">Shall be a scalar with a +<code>LOGICAL</code> type, and it is <code>INTENT(IN)</code>. If it is <code>.true.</code>, +the seed is set to a processor-dependent value that is distinct from th +seed set by a call to <code>RANDOM_INIT</code> in another image. If it is +<code>.false.</code>, the seed is set to a value that does depend which image called +<code>RANDOM_INIT</code>.</td></tr> +</table> + +</dd> +<dt><em>Example</em>:</dt> +<dd><div class="smallexample"> +<pre class="smallexample">program test_random_seed + implicit none + real x(3), y(3) + call random_init(.true., .true.) + call random_number(x) + call random_init(.true., .true.) + call random_number(y) + ! x and y are the same sequence + if (any(x /= y)) call abort +end program test_random_seed +</pre></div> + +</dd> +<dt><em>See also</em>:</dt> +<dd><p><a href="RANDOM_005fNUMBER.html#RANDOM_005fNUMBER">RANDOM_NUMBER</a>, <br> +<a href="RANDOM_005fSEED.html#RANDOM_005fSEED">RANDOM_SEED</a> +</p></dd> +</dl> + + + + + +</body> +</html> |