1 /** @file time_dennyfliegner.cpp
3 * The first test routine implements Denny Fliegner's quick consistency check:
4 * 1) e = (a0 + a1 + a2 + a3 + ...)^2, in expanded form
5 * 2) substitute a0 by (-a2 - a3 - ...) in e
7 * after which e should be just a1^2. */
10 * GiNaC Copyright (C) 1999-2008 Johannes Gutenberg University Mainz, Germany
12 * This program is free software; you can redistribute it and/or modify
13 * it under the terms of the GNU General Public License as published by
14 * the Free Software Foundation; either version 2 of the License, or
15 * (at your option) any later version.
17 * This program is distributed in the hope that it will be useful,
18 * but WITHOUT ANY WARRANTY; without even the implied warranty of
19 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
20 * GNU General Public License for more details.
22 * You should have received a copy of the GNU General Public License
23 * along with this program; if not, write to the Free Software
24 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
33 using namespace GiNaC;
35 static unsigned expand_subs(unsigned size)
38 // create a vector of size symbols named "a0", "a1", ...
41 for (unsigned i=0; i<size; ++i) {
43 buf << "a" << i << ends;
44 a.push_back(symbol(buf.str()));
49 // prepare aux so it will swallow anything but a1^2:
50 aux = -e + a[0] + a[1];
51 e = pow(e,2).expand().subs(a[0]==aux, subs_options::no_pattern).expand();
53 if (e != pow(a[1],2)) {
54 clog << "Denny Fliegner's quick consistency check erroneously returned "
62 unsigned time_dennyfliegner()
66 cout << "timing commutative expansion and substitution" << flush;
68 vector<unsigned> sizes;
77 for (vector<unsigned>::iterator i=sizes.begin(); i!=sizes.end(); ++i) {
79 result += expand_subs(*i);
80 times.push_back(breitling.read());
85 cout << endl << " size: ";
86 for (vector<unsigned>::iterator i=sizes.begin(); i!=sizes.end(); ++i)
88 cout << endl << " time/s:";
89 for (vector<double>::iterator i=times.begin(); i!=times.end(); ++i)
96 extern void randomify_symbol_serials();
98 int main(int argc, char** argv)
100 randomify_symbol_serials();
101 cout << setprecision(2) << showpoint;
102 return time_dennyfliegner();