File: maxima_42.html

package info (click to toggle)
maxima 5.21.1-2squeeze
  • links: PTS
  • area: main
  • in suites: squeeze
  • size: 94,928 kB
  • ctags: 43,849
  • sloc: lisp: 298,974; fortran: 14,666; perl: 14,325; tcl: 10,494; sh: 4,052; makefile: 2,975; ansic: 471; awk: 24; sed: 7
file content (332 lines) | stat: -rw-r--r-- 12,232 bytes parent folder | download
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
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html401/loose.dtd">
<html>
<!-- Created on April, 24 2010 by texi2html 1.76 -->
<!--
Written by: Lionel Cons <Lionel.Cons@cern.ch> (original author)
            Karl Berry  <karl@freefriends.org>
            Olaf Bachmann <obachman@mathematik.uni-kl.de>
            and many others.
Maintained by: Many creative people <dev@texi2html.cvshome.org>
Send bugs and suggestions to <users@texi2html.cvshome.org>

-->
<head>
<title>Maxima 5.21.1 Manual: 42. augmented_lagrangian</title>

<meta name="description" content="Maxima 5.21.1 Manual: 42. augmented_lagrangian">
<meta name="keywords" content="Maxima 5.21.1 Manual: 42. augmented_lagrangian">
<meta name="resource-type" content="document">
<meta name="distribution" content="global">
<meta name="Generator" content="texi2html 1.76">
<meta http-equiv="Content-Type" content="text/html; charset=us-ascii">
<style type="text/css">
<!--
a.summary-letter {text-decoration: none}
pre.display {font-family: serif}
pre.format {font-family: serif}
pre.menu-comment {font-family: serif}
pre.menu-preformatted {font-family: serif}
pre.smalldisplay {font-family: serif; font-size: smaller}
pre.smallexample {font-size: smaller}
pre.smallformat {font-family: serif; font-size: smaller}
pre.smalllisp {font-size: smaller}
span.sansserif {font-family:sans-serif; font-weight:normal;}
ul.toc {list-style: none}
body
{
    color: black;
    background: white; 
    margin-left: 8%;
    margin-right: 13%;
}

h1
{
    margin-left: +8%;
    font-size: 150%;
    font-family: sans-serif
}

h2
{
    font-size: 125%;
    font-family: sans-serif
}

h3
{
    font-size: 100%;
    font-family: sans-serif
}

h2,h3,h4,h5,h6 { margin-left: +4%; }

div.textbox
{
    border: solid;
    border-width: thin;
    /* width: 100%; */
    padding-top: 1em;
    padding-bottom: 1em;
    padding-left: 2em;
    padding-right: 2em
}

div.titlebox
{
    border: none;
    padding-top: 1em;
    padding-bottom: 1em;
    padding-left: 2em;
    padding-right: 2em;
    background: rgb(200,255,255);
    font-family: sans-serif
}

div.synopsisbox
{
    border: none;
    padding-top: 1em;
    padding-bottom: 1em;
    padding-left: 2em;
    padding-right: 2em;
     background: rgb(255,220,255);
    /*background: rgb(200,255,255); */
    /* font-family: fixed */
}

pre.example
{
    border: 1px solid gray;
    padding-top: 1em;
    padding-bottom: 1em;
    padding-left: 1em;
    padding-right: 1em;
    /* background: rgb(247,242,180); */ /* kind of sandy */
    /* background: rgb(200,255,255); */ /* sky blue */
    background-color: #F1F5F9; /* light blue-gray */
    /* font-family: "Lucida Console", monospace */
}

div.spacerbox
{
    border: none;
    padding-top: 2em;
    padding-bottom: 2em
}

div.image
{
    margin: 0;
    padding: 1em;
    text-align: center;
}

div.categorybox
{
    border: 1px solid gray;
    padding-top: 0px;
    padding-bottom: 0px;
    padding-left: 1em;
    padding-right: 1em;
    background: rgb(247,242,220);
}


-->
</style>

<link rel="icon" href="http://maxima.sourceforge.net/favicon.ico"/>
</head>

<body lang="en" bgcolor="#FFFFFF" text="#000000" link="#0000FF" vlink="#800080" alink="#FF0000">

<a name="augmented_005flagrangian"></a>
<a name="SEC187"></a>
<table cellpadding="1" cellspacing="1" border="0">
<tr><td valign="middle" align="left">[<a href="maxima_41.html#SEC186" title="Previous section in reading order"> &lt; </a>]</td>
<td valign="middle" align="left">[<a href="#SEC188" title="Next section in reading order"> &gt; </a>]</td>
<td valign="middle" align="left"> &nbsp; </td>
<td valign="middle" align="left">[<a href="maxima_41.html#SEC183" title="Beginning of this chapter or previous chapter"> &lt;&lt; </a>]</td>
<td valign="middle" align="left">[<a href="maxima.html#SEC_Top" title="Up section"> Up </a>]</td>
<td valign="middle" align="left">[<a href="maxima_43.html#SEC189" title="Next chapter"> &gt;&gt; </a>]</td>
<td valign="middle" align="left"> &nbsp; </td>
<td valign="middle" align="left"> &nbsp; </td>
<td valign="middle" align="left"> &nbsp; </td>
<td valign="middle" align="left"> &nbsp; </td>
<td valign="middle" align="left">[<a href="maxima.html#SEC_Top" title="Cover (top) of document">Top</a>]</td>
<td valign="middle" align="left">[<a href="maxima_toc.html#SEC_Contents" title="Table of contents">Contents</a>]</td>
<td valign="middle" align="left">[<a href="maxima_79.html#SEC331" title="Index">Index</a>]</td>
<td valign="middle" align="left">[<a href="maxima_abt.html#SEC_About" title="About (help)"> ? </a>]</td>
</tr></table>
<h1 class="chapter"> 42. augmented_lagrangian </h1>

<table class="menu" border="0" cellspacing="0">
<tr><td align="left" valign="top"><a href="#SEC188">42.1 Functions and Variables for augmented_lagrangian</a></td><td>&nbsp;&nbsp;</td><td align="left" valign="top">
</td></tr>
</table>

<p><a name="Item_003a-Functions-and-Variables-for-augmented_005flagrangian"></a>
</p><hr size="6">
<a name="Functions-and-Variables-for-augmented_005flagrangian"></a>
<a name="SEC188"></a>
<table cellpadding="1" cellspacing="1" border="0">
<tr><td valign="middle" align="left">[<a href="#SEC187" title="Previous section in reading order"> &lt; </a>]</td>
<td valign="middle" align="left">[<a href="maxima_43.html#SEC189" title="Next section in reading order"> &gt; </a>]</td>
<td valign="middle" align="left"> &nbsp; </td>
<td valign="middle" align="left">[<a href="#SEC187" title="Beginning of this chapter or previous chapter"> &lt;&lt; </a>]</td>
<td valign="middle" align="left">[<a href="#SEC187" title="Up section"> Up </a>]</td>
<td valign="middle" align="left">[<a href="maxima_43.html#SEC189" title="Next chapter"> &gt;&gt; </a>]</td>
<td valign="middle" align="left"> &nbsp; </td>
<td valign="middle" align="left"> &nbsp; </td>
<td valign="middle" align="left"> &nbsp; </td>
<td valign="middle" align="left"> &nbsp; </td>
<td valign="middle" align="left">[<a href="maxima.html#SEC_Top" title="Cover (top) of document">Top</a>]</td>
<td valign="middle" align="left">[<a href="maxima_toc.html#SEC_Contents" title="Table of contents">Contents</a>]</td>
<td valign="middle" align="left">[<a href="maxima_79.html#SEC331" title="Index">Index</a>]</td>
<td valign="middle" align="left">[<a href="maxima_abt.html#SEC_About" title="About (help)"> ? </a>]</td>
</tr></table>
<h2 class="section"> 42.1 Functions and Variables for augmented_lagrangian </h2>

<p><a name="Item_003a-augmented_005flagrangian_005fmethod"></a>
</p><dl>
<dt><u>Function:</u> <b>augmented_lagrangian_method</b><i> (<var>FOM</var>, <var>xx</var>, <var>C</var>, <var>yy</var>)</i>
<a name="IDX1501"></a>
</dt>
<dt><u>Function:</u> <b>augmented_lagrangian_method</b><i> (<var>FOM</var>, <var>xx</var>, <var>C</var>, <var>yy</var>, optional_args)</i>
<a name="IDX1502"></a>
</dt>
<dt><u>Function:</u> <b>augmented_lagrangian_method</b><i> ([<var>FOM</var>, <var>grad</var>], <var>xx</var>, <var>C</var>, <var>yy</var>)</i>
<a name="IDX1503"></a>
</dt>
<dt><u>Function:</u> <b>augmented_lagrangian_method</b><i> ([<var>FOM</var>, <var>grad</var>], <var>xx</var>, <var>C</var>, <var>yy</var>, optional_args)</i>
<a name="IDX1504"></a>
</dt>
<dd><p>Returns an approximate minimum of the expression <var>FOM</var>
with respect to the variables <var>xx</var>,
holding the constraints <var>C</var> equal to zero.
<var>yy</var> is a list of initial guesses for <var>xx</var>.
The method employed is the augmented Lagrangian method (see Refs [1] and [2]).
</p>
<p><var>grad</var>, if present, is the gradient of <var>FOM</var> with respect to <var>xx</var>,
represented as a list of expressions,
one for each variable in <var>xx</var>.
If not present, the gradient is constructed automatically.
</p>
<p><var>FOM</var> and each element of <var>grad</var>, if present,
must be ordinary expressions, not names of functions or lambda expressions.
</p>
<p><code>optional_args</code> represents additional arguments,
specified as <code><var>symbol</var> = <var>value</var></code>.
The optional arguments recognized are:
</p>
<dl compact="compact">
<dt> <code>niter</code></dt>
<dd><p>Number of iterations of the augmented Lagrangian algorithm
</p></dd>
<dt> <code>lbfgs_tolerance</code></dt>
<dd><p>Tolerance supplied to LBFGS
</p></dd>
<dt> <code>iprint</code></dt>
<dd><p>IPRINT parameter (a list of two integers which controls verbosity) supplied to LBFGS
</p></dd>
<dt> <code>%lambda</code></dt>
<dd><p>Initial value of <code>%lambda</code> to be used for calculating the augmented Lagrangian
</p></dd>
</dl>

<p>This implementation minimizes the augmented Lagrangian by
applying the limited-memory BFGS (LBFGS) algorithm,
which is a quasi-Newton algorithm.
</p>
<p><code>load(augmented_lagrangian)</code> loads this function.
</p>
<p>See also <code>lbfgs</code>.
</p>
<p>References:
</p>
<p>[1] <a href="http://www-fp.mcs.anl.gov/otc/Guide/OptWeb/continuous/constrained/nonlinearcon/auglag.html">http://www-fp.mcs.anl.gov/otc/Guide/OptWeb/continuous/constrained/nonlinearcon/auglag.html</a>
</p>
<p>[2] <a href="http://www.cs.ubc.ca/spider/ascher/542/chap10.pdf">http://www.cs.ubc.ca/spider/ascher/542/chap10.pdf</a>
</p>
<p>Examples:
</p>
<pre class="example">(%i1) load (lbfgs);
(%o1)     /maxima/share/lbfgs/lbfgs.mac
(%i2) load (augmented_lagrangian);
(%o2) 
   /maxima/share/contrib/augmented_lagrangian.mac
(%i3) FOM: x^2 + 2*y^2;
                               2    2
(%o3)                       2 y  + x
(%i4) xx: [x, y];
(%o4)                        [x, y]
(%i5) C: [x + y - 1];
(%o5)                      [y + x - 1]
(%i6) yy: [1, 1];
(%o6)                        [1, 1]
(%i7) augmented_lagrangian_method(FOM, xx, C, yy, iprint=[-1,0]);
(%o7) [[x = 0.66665984108002, y = 0.33334027245545], 
                                 %lambda = [- 1.333337940892525]]
</pre>
<p>Same example as before, but this time the gradient is supplied as an argument.
</p>
<pre class="example">(%i1) load (lbfgs)$
(%i2) load (augmented_lagrangian)$
(%i3) FOM: x^2 + 2*y^2;
                               2    2
(%o3)                       2 y  + x
(%i4) FOM: x^2 + 2*y^2;
                               2    2
(%o4)                       2 y  + x
(%i5) xx: [x, y];
(%o5)                        [x, y]
(%i6) grad : [2*x, 4*y];
(%o6)                      [2 x, 4 y]
(%i7) C: [x + y - 1];
(%o7)                      [y + x - 1]
(%i8) yy: [1, 1];
(%o8)                        [1, 1]
(%i9) augmented_lagrangian_method ([FOM, grad], xx, C, yy, iprint = [-1, 0]);
(%o9) [[x = 0.666659841080025, y = .3333402724554462], 
                                 %lambda = [- 1.333337940892543]]
</pre>
<div class=categorybox>


<p>Categories:&nbsp;&nbsp;<a href="maxima_95.html#Category_003a-Numerical-methods">Numerical methods</a>
 &middot;
<a href="maxima_95.html#Category_003a-Share-packages">Share packages</a>
 &middot;
<a href="maxima_95.html#Category_003a-Package-augmented_005flagrangian">Package augmented_lagrangian</a>
</p>
</div>


</dd></dl>


<p><a name="Item_003a-bode"></a>
</p><hr size="6">
<table cellpadding="1" cellspacing="1" border="0">
<tr><td valign="middle" align="left">[<a href="#SEC187" title="Beginning of this chapter or previous chapter"> &lt;&lt; </a>]</td>
<td valign="middle" align="left">[<a href="maxima_43.html#SEC189" title="Next chapter"> &gt;&gt; </a>]</td>
<td valign="middle" align="left"> &nbsp; </td>
<td valign="middle" align="left"> &nbsp; </td>
<td valign="middle" align="left"> &nbsp; </td>
<td valign="middle" align="left"> &nbsp; </td>
<td valign="middle" align="left"> &nbsp; </td>
<td valign="middle" align="left">[<a href="maxima.html#SEC_Top" title="Cover (top) of document">Top</a>]</td>
<td valign="middle" align="left">[<a href="maxima_toc.html#SEC_Contents" title="Table of contents">Contents</a>]</td>
<td valign="middle" align="left">[<a href="maxima_79.html#SEC331" title="Index">Index</a>]</td>
<td valign="middle" align="left">[<a href="maxima_abt.html#SEC_About" title="About (help)"> ? </a>]</td>
</tr></table>
<p>
 <font size="-1">
  This document was generated by <em>Robert Dodier</em> on <em>April, 24 2010</em> using <a href="http://texi2html.cvshome.org/"><em>texi2html 1.76</em></a>.
 </font>
 <br>

</p>
</body>
</html>