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diff --git a/share/doc/gfortran/ETIME.html b/share/doc/gfortran/ETIME.html new file mode 100644 index 0000000..7a669d8 --- /dev/null +++ b/share/doc/gfortran/ETIME.html @@ -0,0 +1,171 @@ +<!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). A copy of the license is included in the section entitled +"GNU Free Documentation License". + +(a) The FSF's Front-Cover Text is: + +A GNU Manual + +(b) The FSF's Back-Cover Text is: + +You have freedom to copy and modify this GNU Manual, like GNU + software. 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: ETIME</title> + +<meta name="description" content="The GNU Fortran Compiler: ETIME"> +<meta name="keywords" content="The GNU Fortran Compiler: ETIME"> +<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="EVENT_005fQUERY.html#EVENT_005fQUERY" rel="next" title="EVENT_QUERY"> +<link href="ERFC_005fSCALED.html#ERFC_005fSCALED" rel="previous" title="ERFC_SCALED"> +<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="ETIME"></a> +<div class="header"> +<p> +Next: <a href="EVENT_005fQUERY.html#EVENT_005fQUERY" accesskey="n" rel="next">EVENT_QUERY</a>, Previous: <a href="ERFC_005fSCALED.html#ERFC_005fSCALED" accesskey="p" rel="previous">ERFC_SCALED</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="ETIME-_002d_002d_002d-Execution-time-subroutine-_0028or-function_0029"></a> +<h3 class="section">8.98 <code>ETIME</code> — Execution time subroutine (or function)</h3> +<a name="index-ETIME"></a> +<a name="index-time_002c-elapsed-2"></a> + +<dl compact="compact"> +<dt><em>Description</em>:</dt> +<dd><p><code>ETIME(VALUES, TIME)</code> returns the number of seconds of runtime +since the start of the process’s execution in <var>TIME</var>. <var>VALUES</var> +returns the user and system components of this time in <code>VALUES(1)</code> and +<code>VALUES(2)</code> respectively. <var>TIME</var> is equal to <code>VALUES(1) + VALUES(2)</code>. +</p> +<p>On some systems, the underlying timings are represented using types with +sufficiently small limits that overflows (wrap around) are possible, such as +32-bit types. Therefore, the values returned by this intrinsic might be, or +become, negative, or numerically less than previous values, during a single +run of the compiled program. +</p> +<p>This intrinsic is provided in both subroutine and function forms; however, +only one form can be used in any given program unit. +</p> +<p><var>VALUES</var> and <var>TIME</var> are <code>INTENT(OUT)</code> and provide the following: +</p> +<table> +<tr><td width="15%"><code>VALUES(1)</code>:</td><td width="70%">User time in seconds.</td></tr> +<tr><td width="15%"><code>VALUES(2)</code>:</td><td width="70%">System time in seconds.</td></tr> +<tr><td width="15%"><code>TIME</code>:</td><td width="70%">Run time since start in seconds.</td></tr> +</table> + +</dd> +<dt><em>Standard</em>:</dt> +<dd><p>GNU extension +</p> +</dd> +<dt><em>Class</em>:</dt> +<dd><p>Subroutine, function +</p> +</dd> +<dt><em>Syntax</em>:</dt> +<dd><table> +<tr><td width="80%"><code>CALL ETIME(VALUES, TIME)</code>.</td></tr> +<tr><td width="80%"><code>TIME = ETIME(VALUES)</code>, (not recommended).</td></tr> +</table> + +</dd> +<dt><em>Arguments</em>:</dt> +<dd><table> +<tr><td width="15%"><var>VALUES</var></td><td width="70%">The type shall be <code>REAL(4), DIMENSION(2)</code>.</td></tr> +<tr><td width="15%"><var>TIME</var></td><td width="70%">The type shall be <code>REAL(4)</code>.</td></tr> +</table> + +</dd> +<dt><em>Return value</em>:</dt> +<dd><p>Elapsed time in seconds since the start of program execution. +</p> +</dd> +<dt><em>Example</em>:</dt> +<dd><div class="smallexample"> +<pre class="smallexample">program test_etime + integer(8) :: i, j + real, dimension(2) :: tarray + real :: result + call ETIME(tarray, result) + print *, result + print *, tarray(1) + print *, tarray(2) + do i=1,100000000 ! Just a delay + j = i * i - i + end do + call ETIME(tarray, result) + print *, result + print *, tarray(1) + print *, tarray(2) +end program test_etime +</pre></div> + +</dd> +<dt><em>See also</em>:</dt> +<dd><p><a href="CPU_005fTIME.html#CPU_005fTIME">CPU_TIME</a> +</p> +</dd> +</dl> + + + +<hr> +<div class="header"> +<p> +Next: <a href="EVENT_005fQUERY.html#EVENT_005fQUERY" accesskey="n" rel="next">EVENT_QUERY</a>, Previous: <a href="ERFC_005fSCALED.html#ERFC_005fSCALED" accesskey="p" rel="previous">ERFC_SCALED</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> + + + +</body> +</html> |