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A copy of the license is included in the 12section entitled "GNU Free Documentation License". 13 --> 14<!-- Created by GNU Texinfo 5.1, http://www.gnu.org/software/texinfo/ --> 15<head> 16<title>Using as: Flonums</title> 17 18<meta name="description" content="Using as: Flonums"> 19<meta name="keywords" content="Using as: Flonums"> 20<meta name="resource-type" content="document"> 21<meta name="distribution" content="global"> 22<meta name="Generator" content="makeinfo"> 23<meta http-equiv="Content-Type" content="text/html; charset=utf-8"> 24<link href="index.html#Top" rel="start" title="Top"> 25<link href="AS-Index.html#AS-Index" rel="index" title="AS Index"> 26<link href="index.html#SEC_Contents" rel="contents" title="Table of Contents"> 27<link href="Numbers.html#Numbers" rel="up" title="Numbers"> 28<link href="Sections.html#Sections" rel="next" title="Sections"> 29<link href="Bignums.html#Bignums" rel="previous" title="Bignums"> 30<style type="text/css"> 31<!-- 32a.summary-letter {text-decoration: none} 33blockquote.smallquotation {font-size: smaller} 34div.display {margin-left: 3.2em} 35div.example {margin-left: 3.2em} 36div.indentedblock {margin-left: 3.2em} 37div.lisp {margin-left: 3.2em} 38div.smalldisplay {margin-left: 3.2em} 39div.smallexample {margin-left: 3.2em} 40div.smallindentedblock {margin-left: 3.2em; font-size: smaller} 41div.smalllisp {margin-left: 3.2em} 42kbd {font-style:oblique} 43pre.display {font-family: inherit} 44pre.format {font-family: inherit} 45pre.menu-comment {font-family: serif} 46pre.menu-preformatted {font-family: serif} 47pre.smalldisplay {font-family: inherit; font-size: smaller} 48pre.smallexample {font-size: smaller} 49pre.smallformat {font-family: inherit; font-size: smaller} 50pre.smalllisp {font-size: smaller} 51span.nocodebreak {white-space:nowrap} 52span.nolinebreak {white-space:nowrap} 53span.roman {font-family:serif; font-weight:normal} 54span.sansserif {font-family:sans-serif; font-weight:normal} 55ul.no-bullet {list-style: none} 56--> 57</style> 58 59 60</head> 61 62<body lang="en" bgcolor="#FFFFFF" text="#000000" link="#0000FF" vlink="#800080" alink="#FF0000"> 63<a name="Flonums"></a> 64<div class="header"> 65<p> 66Previous: <a href="Bignums.html#Bignums" accesskey="p" rel="previous">Bignums</a>, Up: <a href="Numbers.html#Numbers" accesskey="u" rel="up">Numbers</a> [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="AS-Index.html#AS-Index" title="Index" rel="index">Index</a>]</p> 67</div> 68<hr> 69<a name="Flonums-1"></a> 70<h4 class="subsubsection">3.6.2.3 Flonums</h4> 71<a name="index-flonums"></a> 72<a name="index-floating-point-numbers"></a> 73<a name="index-constants_002c-floating-point"></a> 74 75<a name="index-precision_002c-floating-point"></a> 76<p>A <em>flonum</em> represents a floating point number. The translation is 77indirect: a decimal floating point number from the text is converted by 78<code>as</code> to a generic binary floating point number of more than 79sufficient precision. This generic floating point number is converted 80to a particular computer’s floating point format (or formats) by a 81portion of <code>as</code> specialized to that computer. 82</p> 83<p>A flonum is written by writing (in order) 84</p><ul> 85<li> The digit ‘<samp>0</samp>’. 86(‘<samp>0</samp>’ is optional on the HPPA.) 87 88</li><li> A letter, to tell <code>as</code> the rest of the number is a flonum. 89<kbd>e</kbd> is recommended. Case is not important. 90 91<p>On the H8/300 and Renesas / SuperH SH architectures, the letter must be 92one of the letters ‘<samp>DFPRSX</samp>’ (in upper or lower case). 93</p> 94<p>On the ARC, the letter must be one of the letters ‘<samp>DFRS</samp>’ 95(in upper or lower case). 96</p> 97<p>On the HPPA architecture, the letter must be ‘<samp>E</samp>’ (upper case only). 98</p> 99</li><li> An optional sign: either ‘<samp>+</samp>’ or ‘<samp>-</samp>’. 100 101</li><li> An optional <em>integer part</em>: zero or more decimal digits. 102 103</li><li> An optional <em>fractional part</em>: ‘<samp>.</samp>’ followed by zero 104or more decimal digits. 105 106</li><li> An optional exponent, consisting of: 107 108<ul> 109<li> An ‘<samp>E</samp>’ or ‘<samp>e</samp>’. 110</li><li> Optional sign: either ‘<samp>+</samp>’ or ‘<samp>-</samp>’. 111</li><li> One or more decimal digits. 112</li></ul> 113 114</li></ul> 115 116<p>At least one of the integer part or the fractional part must be 117present. The floating point number has the usual base-10 value. 118</p> 119<p><code>as</code> does all processing using integers. Flonums are computed 120independently of any floating point hardware in the computer running 121<code>as</code>. 122</p> 123 124 125 126</body> 127</html> 128