1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
|
<html><head><title>XLISP *float-format*</title>
<link rel="stylesheet" type="text/css" href="reference.css">
</head>
<body>
<a href="../start.htm">Nyquist / XLISP 2.0</a> -
<a href="../manual/contents.htm">Contents</a> |
<a href="../tutorials/tutorials.htm">Tutorials</a> |
<a href="../examples/examples.htm">Examples</a> |
<a href="reference-index.htm">Reference</a>
<hr>
<h1>*float-format*</h1>
<hr>
<p><table cellpadding="0" cellspacing="0" style="margin-left:10px"><tbody>
<tr valign="top">
<td><nobr>Type:</nobr></td>
<td><nobr> - </nobr></td>
<td width="100%"><nobr>system variable</nobr></td>
</tr>
<tr valign="top">
<td><nobr>Source:</nobr></td>
<td><nobr> - </nobr></td>
<td width="100%"><nobr>xlprin.c</nobr></td>
</tr>
</tbody></table></p>
<h2>Syntax</h2>
<dl>
<dt> *float-format*</dt>
<dd>returns - the print format for <nobr>floating-point</nobr> numbers</dd>
</dl>
<h2>Description</h2>
<p> *float-format* is a system variable that allows a user to specify how
floating point numbers are to be printed by XLISP. The value of
*float-format* should be set to one of the string expressions
"%e", "%f" or "%g". These format strings are
similar to C-language floating point specifications:</p>
<p><table cellpadding="0" cellspacing="0"><tbody>
<tr valign="top">
<td><nobr><code> "%e"</code></nobr></td>
<td><nobr> -<code> </code></nobr></td>
<td width="100%">exponential. The number is converted to decimal notation
of the form:
<pre class="example">
[-]<font color="#0000CC"><i>m</i></font>.<font color="#0000CC"><i>nnnnnn</i></font>E[+-]<font color="#0000CC"><i>xx</i></font>
</pre>
There is one leading digit. There are 6 digits after the decimal
point.</td>
</tr>
<tr>
<td><nobr><font size="-2"> </font></nobr></td>
</tr>
<tr valign="top">
<td><nobr><code> "%f"</code></nobr></td>
<td><nobr> -<code> </code></nobr></td>
<td width="100%">decimal. The number is converted to decimal notation of
the form:
<pre class="example">
[-]<font color="#0000CC"><i>mmmmmm</i></font>.<font color="#0000CC"><i>nnnnnn</i></font>
</pre>
There are as many digits before the decimal point as necessary. There
are 6 digits after the decimal point.</td>
</tr>
<tr>
<td><nobr><font size="-2"> </font></nobr></td>
</tr>
<tr valign="top">
<td><nobr><code> "%g"</code></nobr></td>
<td><nobr> -<code> </code></nobr></td>
<td width="100%">shortest. The number is converted to either the form of
"%e" or "%f", whichever produces the shortest output
string. Non-significant zeroes are not printed.</td>
</tr>
</tbody></table></p>
<p> The default value for *float-format* is the string "%g".</p>
<p>There are several additional flags and options available:</p>
<p><table cellpadding="0" cellspacing="0"><tbody>
<tr>
<td><nobr><code> </code></nobr></td>
<td><nobr><code> +</code></nobr></td>
<td><nobr> <code> </code>-<code> </code></nobr></td>
<td width="100%"><nobr>always print the sign</nobr></td>
</tr>
<tr>
<td><nobr><code> </code></nobr></td>
<td><nobr><code><i>space</i></code></nobr></td>
<td><nobr> <code> </code>-<code> </code></nobr></td>
<td width="100%"><nobr>print a space instead of a + sign</nobr></td>
</tr>
<tr>
<td><nobr><code> </code></nobr></td>
<td><nobr><code> #</code></nobr></td>
<td><nobr> <code> </code>-<code> </code></nobr></td>
<td width="100%"><nobr>always print the dot, do not remove zeros after the dot</nobr></td>
</tr>
<tr>
<td><nobr><code> </code></nobr></td>
<td><nobr><code> .<i>n</i></code></nobr></td>
<td><nobr> <code> </code>-<code> </code></nobr></td>
<td width="100%"><nobr>number of digits after the dot</nobr></td>
</tr>
</tbody></table></p>
<p>The flags and options must be written between the "%" and the
formatting letter, as shown in the examples below.</p>
<h2>Examples</h2>
<pre class="example">
(setq *float-format* "%e") <font color="#008844">; exponential notation</font>
(print 1.0) => 1.000000e+00
(print -9e99) => -9.000000e+99
(setq *float-format* "%f") <font color="#008844">; decimal notation</font>
(print 1.0) => 1.000000
(print 1.0e4) => 10000.000000
(print -999.99e-99) => -0.000000</font>
(setq *float-format* "%g") <font color="#008844">; shortest notation</font>
(print 1.0) => 1
(print 1.0e7) => 1e+07
(print -999.999e99) => -9.99999e+101
(setq *float-format* "%+g") <font color="#008844">; always print the sign</font>
(print 1.1) => +1.1
(print -1.1) => -1.1
(setq *float-format* "% g") <font color="#008844">; print a space instead of the + sign</font>
(print 1.1) => 1.1
(print -1.1) => -1.1
(setq *float-format* "%#.10g") <font color="#008844">; ten digits after the dot</font>
(print 1.0) => 1.000000000
(print 1.0e7) => 10000000.00
(print -999.9999999e99) => -9.999999999e+101
(setq *float-format* "%+#.10g") <font color="#008844">; ten digits after the dot plus sign</font>
(print 1.2345) => +1.234500000
(print -1.2345) => -1.234500000
(setq *float-format* "%%") <font color="#008844">; bad format</font>
(print 1.0) => %%
(setq *float-format* "%g") <font color="#008844">; reset to shortest notation</font>
</pre>
<p><b>Note:</b> The string in the <nobr>*float-format*</nobr> variable is
the format specifier for the the underlying 'sprintf'
<nobr>C-function</nobr>.</p>
<p><nobr> <a href="#top">Back to Top</nobr></a></p>
<hr>
<a href="../start.htm">Nyquist / XLISP 2.0</a> -
<a href="../manual/contents.htm">Contents</a> |
<a href="../tutorials/tutorials.htm">Tutorials</a> |
<a href="../examples/examples.htm">Examples</a> |
<a href="reference-index.htm">Reference</a>
</body></html>
|
