1 /** @file time_lw_H.cpp
3 * Test H from the paper "Comparison of Polynomial-Oriented CAS" by Robert H.
4 * Lewis and Michael Wester. */
7 * GiNaC Copyright (C) 1999-2008 Johannes Gutenberg University Mainz, Germany
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License as published by
11 * the Free Software Foundation; either version 2 of the License, or
12 * (at your option) any later version.
14 * This program is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 * GNU General Public License for more details.
19 * You should have received a copy of the GNU General Public License
20 * along with this program; if not, write to the Free Software
21 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
29 using namespace GiNaC;
31 static unsigned test(unsigned n)
35 for (unsigned r=0; r<n; ++r)
36 for (unsigned c=0; c<n; ++c)
37 hilbert.set(r,c,numeric(1,r+c+1));
38 ex det = hilbert.determinant();
41 The closed form of the determinant of n x n Hilbert matrices is:
44 ----- | pow(factorial(r),3) |
45 | | | ------------------- |
46 | | | factorial(r+n) |
51 for (unsigned r=0; r<n; ++r)
52 hilbdet *= pow(factorial(r),3)/(factorial(r+n));
55 clog << "determinant of " << n << "x" << n << " erroneously returned " << det << endl;
68 cout << "timing Lewis-Wester test H (det of 80x80 Hilbert)" << flush;
71 // correct for very small times:
75 } while ((time=rolex.read())<0.1 && !result);
77 cout << time/count << 's' << endl;
82 extern void randomify_symbol_serials();
84 int main(int argc, char** argv)
86 randomify_symbol_serials();
87 cout << setprecision(2) << showpoint;