annotate src/fftw-3.3.8/doc/html/Wisdom-of-Fortran_003f.html @ 169:223a55898ab9 tip default

Add null config files
author Chris Cannam <cannam@all-day-breakfast.com>
date Mon, 02 Mar 2020 14:03:47 +0000
parents bd3cc4d1df30
children
rev   line source
cannam@167 1 <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
cannam@167 2 <html>
cannam@167 3 <!-- This manual is for FFTW
cannam@167 4 (version 3.3.8, 24 May 2018).
cannam@167 5
cannam@167 6 Copyright (C) 2003 Matteo Frigo.
cannam@167 7
cannam@167 8 Copyright (C) 2003 Massachusetts Institute of Technology.
cannam@167 9
cannam@167 10 Permission is granted to make and distribute verbatim copies of this
cannam@167 11 manual provided the copyright notice and this permission notice are
cannam@167 12 preserved on all copies.
cannam@167 13
cannam@167 14 Permission is granted to copy and distribute modified versions of this
cannam@167 15 manual under the conditions for verbatim copying, provided that the
cannam@167 16 entire resulting derived work is distributed under the terms of a
cannam@167 17 permission notice identical to this one.
cannam@167 18
cannam@167 19 Permission is granted to copy and distribute translations of this manual
cannam@167 20 into another language, under the above conditions for modified versions,
cannam@167 21 except that this permission notice may be stated in a translation
cannam@167 22 approved by the Free Software Foundation. -->
cannam@167 23 <!-- Created by GNU Texinfo 6.3, http://www.gnu.org/software/texinfo/ -->
cannam@167 24 <head>
cannam@167 25 <title>FFTW 3.3.8: Wisdom of Fortran?</title>
cannam@167 26
cannam@167 27 <meta name="description" content="FFTW 3.3.8: Wisdom of Fortran?">
cannam@167 28 <meta name="keywords" content="FFTW 3.3.8: Wisdom of Fortran?">
cannam@167 29 <meta name="resource-type" content="document">
cannam@167 30 <meta name="distribution" content="global">
cannam@167 31 <meta name="Generator" content="makeinfo">
cannam@167 32 <meta http-equiv="Content-Type" content="text/html; charset=utf-8">
cannam@167 33 <link href="index.html#Top" rel="start" title="Top">
cannam@167 34 <link href="Concept-Index.html#Concept-Index" rel="index" title="Concept Index">
cannam@167 35 <link href="index.html#SEC_Contents" rel="contents" title="Table of Contents">
cannam@167 36 <link href="Calling-FFTW-from-Legacy-Fortran.html#Calling-FFTW-from-Legacy-Fortran" rel="up" title="Calling FFTW from Legacy Fortran">
cannam@167 37 <link href="Upgrading-from-FFTW-version-2.html#Upgrading-from-FFTW-version-2" rel="next" title="Upgrading from FFTW version 2">
cannam@167 38 <link href="Fortran-Examples.html#Fortran-Examples" rel="prev" title="Fortran Examples">
cannam@167 39 <style type="text/css">
cannam@167 40 <!--
cannam@167 41 a.summary-letter {text-decoration: none}
cannam@167 42 blockquote.indentedblock {margin-right: 0em}
cannam@167 43 blockquote.smallindentedblock {margin-right: 0em; font-size: smaller}
cannam@167 44 blockquote.smallquotation {font-size: smaller}
cannam@167 45 div.display {margin-left: 3.2em}
cannam@167 46 div.example {margin-left: 3.2em}
cannam@167 47 div.lisp {margin-left: 3.2em}
cannam@167 48 div.smalldisplay {margin-left: 3.2em}
cannam@167 49 div.smallexample {margin-left: 3.2em}
cannam@167 50 div.smalllisp {margin-left: 3.2em}
cannam@167 51 kbd {font-style: oblique}
cannam@167 52 pre.display {font-family: inherit}
cannam@167 53 pre.format {font-family: inherit}
cannam@167 54 pre.menu-comment {font-family: serif}
cannam@167 55 pre.menu-preformatted {font-family: serif}
cannam@167 56 pre.smalldisplay {font-family: inherit; font-size: smaller}
cannam@167 57 pre.smallexample {font-size: smaller}
cannam@167 58 pre.smallformat {font-family: inherit; font-size: smaller}
cannam@167 59 pre.smalllisp {font-size: smaller}
cannam@167 60 span.nolinebreak {white-space: nowrap}
cannam@167 61 span.roman {font-family: initial; font-weight: normal}
cannam@167 62 span.sansserif {font-family: sans-serif; font-weight: normal}
cannam@167 63 ul.no-bullet {list-style: none}
cannam@167 64 -->
cannam@167 65 </style>
cannam@167 66
cannam@167 67
cannam@167 68 </head>
cannam@167 69
cannam@167 70 <body lang="en">
cannam@167 71 <a name="Wisdom-of-Fortran_003f"></a>
cannam@167 72 <div class="header">
cannam@167 73 <p>
cannam@167 74 Previous: <a href="Fortran-Examples.html#Fortran-Examples" accesskey="p" rel="prev">Fortran Examples</a>, Up: <a href="Calling-FFTW-from-Legacy-Fortran.html#Calling-FFTW-from-Legacy-Fortran" accesskey="u" rel="up">Calling FFTW from Legacy Fortran</a> &nbsp; [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Concept-Index.html#Concept-Index" title="Index" rel="index">Index</a>]</p>
cannam@167 75 </div>
cannam@167 76 <hr>
cannam@167 77 <a name="Wisdom-of-Fortran_003f-1"></a>
cannam@167 78 <h3 class="section">8.5 Wisdom of Fortran?</h3>
cannam@167 79
cannam@167 80 <p>In this section, we discuss how one can import/export FFTW wisdom
cannam@167 81 (saved plans) to/from a Fortran program; we assume that the reader is
cannam@167 82 already familiar with wisdom, as described in <a href="Words-of-Wisdom_002dSaving-Plans.html#Words-of-Wisdom_002dSaving-Plans">Words of Wisdom-Saving Plans</a>.
cannam@167 83 </p>
cannam@167 84 <a name="index-portability-8"></a>
cannam@167 85 <p>The basic problem is that is difficult to (portably) pass files and
cannam@167 86 strings between Fortran and C, so we cannot provide a direct Fortran
cannam@167 87 equivalent to the <code>fftw_export_wisdom_to_file</code>, etcetera,
cannam@167 88 functions. Fortran interfaces <em>are</em> provided for the functions
cannam@167 89 that do not take file/string arguments, however:
cannam@167 90 <code>dfftw_import_system_wisdom</code>, <code>dfftw_import_wisdom</code>,
cannam@167 91 <code>dfftw_export_wisdom</code>, and <code>dfftw_forget_wisdom</code>.
cannam@167 92 <a name="index-dfftw_005fimport_005fsystem_005fwisdom"></a>
cannam@167 93 <a name="index-dfftw_005fimport_005fwisdom"></a>
cannam@167 94 <a name="index-dfftw_005fexport_005fwisdom"></a>
cannam@167 95 <a name="index-dfftw_005fforget_005fwisdom"></a>
cannam@167 96 </p>
cannam@167 97
cannam@167 98 <p>So, for example, to import the system-wide wisdom, you would do:
cannam@167 99 </p>
cannam@167 100 <div class="example">
cannam@167 101 <pre class="example"> integer isuccess
cannam@167 102 call dfftw_import_system_wisdom(isuccess)
cannam@167 103 </pre></div>
cannam@167 104
cannam@167 105 <p>As usual, the C return value is turned into a first parameter;
cannam@167 106 <code>isuccess</code> is non-zero on success and zero on failure (e.g. if
cannam@167 107 there is no system wisdom installed).
cannam@167 108 </p>
cannam@167 109 <p>If you want to import/export wisdom from/to an arbitrary file or
cannam@167 110 elsewhere, you can employ the generic <code>dfftw_import_wisdom</code> and
cannam@167 111 <code>dfftw_export_wisdom</code> functions, for which you must supply a
cannam@167 112 subroutine to read/write one character at a time. The FFTW package
cannam@167 113 contains an example file <code>doc/f77_wisdom.f</code> demonstrating how to
cannam@167 114 implement <code>import_wisdom_from_file</code> and
cannam@167 115 <code>export_wisdom_to_file</code> subroutines in this way. (These routines
cannam@167 116 cannot be compiled into the FFTW library itself, lest all FFTW-using
cannam@167 117 programs be required to link with the Fortran I/O library.)
cannam@167 118 </p>
cannam@167 119
cannam@167 120
cannam@167 121 </body>
cannam@167 122 </html>