Merge branch 'no-edges2'
[libdai.git] / src / util.cpp
1 /* Copyright (C) 2006-2008 Joris Mooij [j dot mooij at science dot ru dot nl]
2 Radboud University Nijmegen, The Netherlands
3
4 This file is part of libDAI.
5
6 libDAI is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 2 of the License, or
9 (at your option) any later version.
10
11 libDAI is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
15
16 You should have received a copy of the GNU General Public License
17 along with libDAI; if not, write to the Free Software
18 Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
19 */
20
21
22 #include <dai/util.h>
23 #include <boost/random/linear_congruential.hpp>
24 #include <boost/random/uniform_real.hpp>
25 #include <boost/random/normal_distribution.hpp>
26 #include <boost/random/variate_generator.hpp>
27
28
29 namespace dai {
30
31
32 clock_t toc() {
33 tms tbuf;
34 times(&tbuf);
35 return( tbuf.tms_utime );
36 }
37
38
39 // This is a typedef for a random number generator.
40 // Try boost::mt19937 or boost::ecuyer1988 instead of boost::minstd_rand
41 typedef boost::minstd_rand _rnd_gen_type;
42
43 _rnd_gen_type _rnd_gen(42);
44
45 // Define a uniform random number distribution which produces "double"
46 // values between 0 and 1 (0 inclusive, 1 exclusive).
47 boost::uniform_real<> _uni_dist(0,1);
48 boost::variate_generator<_rnd_gen_type&, boost::uniform_real<> > _uni_rnd(_rnd_gen, _uni_dist);
49
50 // Define a normal distribution with mean 0 and standard deviation 1.
51 boost::normal_distribution<> _normal_dist;
52 boost::variate_generator<_rnd_gen_type&, boost::normal_distribution<> > _normal_rnd(_rnd_gen, _normal_dist);
53
54
55 void rnd_seed( int seed ) {
56 _rnd_gen.seed(seed);
57 }
58
59 double rnd_uniform() {
60 return _uni_rnd();
61 }
62
63 double rnd_stdnormal() {
64 return _normal_rnd();
65 }
66
67
68 } // end of namespace dai