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
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
|
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<!-- Copyright (C) 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012, 2013 The GSL Team.
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 no
Invariant Sections and no cover texts. A copy of the license is
included in the section entitled "GNU Free Documentation License". -->
<!-- Created by GNU Texinfo 5.1, http://www.gnu.org/software/texinfo/ -->
<head>
<title>GNU Scientific Library – Reference Manual: Simulated Annealing functions</title>
<meta name="description" content="GNU Scientific Library – Reference Manual: Simulated Annealing functions">
<meta name="keywords" content="GNU Scientific Library – Reference Manual: Simulated Annealing functions">
<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="Function-Index.html#Function-Index" rel="index" title="Function Index">
<link href="Simulated-Annealing.html#Simulated-Annealing" rel="up" title="Simulated Annealing">
<link href="Examples-with-Simulated-Annealing.html#Examples-with-Simulated-Annealing" rel="next" title="Examples with Simulated Annealing">
<link href="Simulated-Annealing-algorithm.html#Simulated-Annealing-algorithm" rel="previous" title="Simulated Annealing algorithm">
<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="Simulated-Annealing-functions"></a>
<div class="header">
<p>
Next: <a href="Examples-with-Simulated-Annealing.html#Examples-with-Simulated-Annealing" accesskey="n" rel="next">Examples with Simulated Annealing</a>, Previous: <a href="Simulated-Annealing-algorithm.html#Simulated-Annealing-algorithm" accesskey="p" rel="previous">Simulated Annealing algorithm</a>, Up: <a href="Simulated-Annealing.html#Simulated-Annealing" accesskey="u" rel="up">Simulated Annealing</a> [<a href="Function-Index.html#Function-Index" title="Index" rel="index">Index</a>]</p>
</div>
<hr>
<a name="Simulated-Annealing-functions-1"></a>
<h3 class="section">25.2 Simulated Annealing functions</h3>
<dl>
<dt><a name="index-gsl_005fsiman_005fsolve"></a>Function: <em>void</em> <strong>gsl_siman_solve</strong> <em>(const gsl_rng * <var>r</var>, void * <var>x0_p</var>, gsl_siman_Efunc_t <var>Ef</var>, gsl_siman_step_t <var>take_step</var>, gsl_siman_metric_t <var>distance</var>, gsl_siman_print_t <var>print_position</var>, gsl_siman_copy_t <var>copyfunc</var>, gsl_siman_copy_construct_t <var>copy_constructor</var>, gsl_siman_destroy_t <var>destructor</var>, size_t <var>element_size</var>, gsl_siman_params_t <var>params</var>)</em></dt>
<dd>
<p>This function performs a simulated annealing search through a given
space. The space is specified by providing the functions <var>Ef</var> and
<var>distance</var>. The simulated annealing steps are generated using the
random number generator <var>r</var> and the function <var>take_step</var>.
</p>
<p>The starting configuration of the system should be given by <var>x0_p</var>.
The routine offers two modes for updating configurations, a fixed-size
mode and a variable-size mode. In the fixed-size mode the configuration
is stored as a single block of memory of size <var>element_size</var>.
Copies of this configuration are created, copied and destroyed
internally using the standard library functions <code>malloc</code>,
<code>memcpy</code> and <code>free</code>. The function pointers <var>copyfunc</var>,
<var>copy_constructor</var> and <var>destructor</var> should be null pointers in
fixed-size mode. In the variable-size mode the functions
<var>copyfunc</var>, <var>copy_constructor</var> and <var>destructor</var> are used to
create, copy and destroy configurations internally. The variable
<var>element_size</var> should be zero in the variable-size mode.
</p>
<p>The <var>params</var> structure (described below) controls the run by
providing the temperature schedule and other tunable parameters to the
algorithm.
</p>
<p>On exit the best result achieved during the search is placed in
<code>*<var>x0_p</var></code>. If the annealing process has been successful this
should be a good approximation to the optimal point in the space.
</p>
<p>If the function pointer <var>print_position</var> is not null, a debugging
log will be printed to <code>stdout</code> with the following columns:
</p>
<div class="example">
<pre class="example">#-iter #-evals temperature position energy best_energy
</pre></div>
<p>and the output of the function <var>print_position</var> itself. If
<var>print_position</var> is null then no information is printed.
</p></dd></dl>
<p>The simulated annealing routines require several user-specified
functions to define the configuration space and energy function. The
prototypes for these functions are given below.
</p>
<dl>
<dt><a name="index-gsl_005fsiman_005fEfunc_005ft"></a>Data Type: <strong>gsl_siman_Efunc_t</strong></dt>
<dd><p>This function type should return the energy of a configuration <var>xp</var>.
</p>
<div class="example">
<pre class="example">double (*gsl_siman_Efunc_t) (void *xp)
</pre></div>
</dd></dl>
<dl>
<dt><a name="index-gsl_005fsiman_005fstep_005ft"></a>Data Type: <strong>gsl_siman_step_t</strong></dt>
<dd><p>This function type should modify the configuration <var>xp</var> using a random step
taken from the generator <var>r</var>, up to a maximum distance of
<var>step_size</var>.
</p>
<div class="example">
<pre class="example">void (*gsl_siman_step_t) (const gsl_rng *r, void *xp,
double step_size)
</pre></div>
</dd></dl>
<dl>
<dt><a name="index-gsl_005fsiman_005fmetric_005ft"></a>Data Type: <strong>gsl_siman_metric_t</strong></dt>
<dd><p>This function type should return the distance between two configurations
<var>xp</var> and <var>yp</var>.
</p>
<div class="example">
<pre class="example">double (*gsl_siman_metric_t) (void *xp, void *yp)
</pre></div>
</dd></dl>
<dl>
<dt><a name="index-gsl_005fsiman_005fprint_005ft"></a>Data Type: <strong>gsl_siman_print_t</strong></dt>
<dd><p>This function type should print the contents of the configuration <var>xp</var>.
</p>
<div class="example">
<pre class="example">void (*gsl_siman_print_t) (void *xp)
</pre></div>
</dd></dl>
<dl>
<dt><a name="index-gsl_005fsiman_005fcopy_005ft"></a>Data Type: <strong>gsl_siman_copy_t</strong></dt>
<dd><p>This function type should copy the configuration <var>source</var> into <var>dest</var>.
</p>
<div class="example">
<pre class="example">void (*gsl_siman_copy_t) (void *source, void *dest)
</pre></div>
</dd></dl>
<dl>
<dt><a name="index-gsl_005fsiman_005fcopy_005fconstruct_005ft"></a>Data Type: <strong>gsl_siman_copy_construct_t</strong></dt>
<dd><p>This function type should create a new copy of the configuration <var>xp</var>.
</p>
<div class="example">
<pre class="example">void * (*gsl_siman_copy_construct_t) (void *xp)
</pre></div>
</dd></dl>
<dl>
<dt><a name="index-gsl_005fsiman_005fdestroy_005ft"></a>Data Type: <strong>gsl_siman_destroy_t</strong></dt>
<dd><p>This function type should destroy the configuration <var>xp</var>, freeing its
memory.
</p>
<div class="example">
<pre class="example">void (*gsl_siman_destroy_t) (void *xp)
</pre></div>
</dd></dl>
<dl>
<dt><a name="index-gsl_005fsiman_005fparams_005ft"></a>Data Type: <strong>gsl_siman_params_t</strong></dt>
<dd><p>These are the parameters that control a run of <code>gsl_siman_solve</code>.
This structure contains all the information needed to control the
search, beyond the energy function, the step function and the initial
guess.
</p>
<dl compact="compact">
<dt><code>int n_tries</code></dt>
<dd><p>The number of points to try for each step.
</p>
</dd>
<dt><code>int iters_fixed_T</code></dt>
<dd><p>The number of iterations at each temperature.
</p>
</dd>
<dt><code>double step_size</code></dt>
<dd><p>The maximum step size in the random walk.
</p>
</dd>
<dt><code>double k, t_initial, mu_t, t_min</code></dt>
<dd><p>The parameters of the Boltzmann distribution and cooling schedule.
</p></dd>
</dl>
</dd></dl>
<hr>
<div class="header">
<p>
Next: <a href="Examples-with-Simulated-Annealing.html#Examples-with-Simulated-Annealing" accesskey="n" rel="next">Examples with Simulated Annealing</a>, Previous: <a href="Simulated-Annealing-algorithm.html#Simulated-Annealing-algorithm" accesskey="p" rel="previous">Simulated Annealing algorithm</a>, Up: <a href="Simulated-Annealing.html#Simulated-Annealing" accesskey="u" rel="up">Simulated Annealing</a> [<a href="Function-Index.html#Function-Index" title="Index" rel="index">Index</a>]</p>
</div>
</body>
</html>
|
