linbox
examples/sparseelimdet.C

Gaussian elimination determinant of sparse matrix over Z or Zp.

/*
* examples/sparseelimdet.C
*
* Copyright (C) 2006, 2010 J-G Dumas
* ========LICENCE========
* This file is part of the library LinBox.
*
* LinBox is free software: you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
* ========LICENCE========
*/
#include <iostream>
#include <vector>
#include <utility>
#include <linbox/field/gf2.h>
#include <linbox/blackbox/zero-one.h>
#include <linbox/solutions/rank.h>
using namespace LinBox;
using namespace std;
int main (int argc, char **argv)
{
commentator().setMaxDetailLevel (-1);
commentator().setMaxDepth (-1);
commentator().setReportStream (std::cerr);
if (argc < 2 || argc > 3)
{ cerr << "Usage: sparseelimdet <matrix-file-in-supported-format> [<p>]" << endl; return -1; }
ifstream input (argv[1]);
if (!input) { cerr << "Error opening matrix file: " << argv[1] << endl; return -1; }
if (argc == 2) { // determinant over the integers.
Givaro::ZRing<Integer> ZZ;
SparseMatrix<Givaro::ZRing<Integer> > A ( ZZ );
A.read(input);
cout << "A is " << A.rowdim() << " by " << A.coldim() << endl;
SE.strategy(Specifier::PIVOT_LINEAR);
Givaro::ZRing<Integer>::Element d;
det (d, A, SE);
ZZ.write(cout << "Determinant is ", d) << endl;
}
if (argc == 3) { // determinant over a finite field
typedef Givaro::Modular<double> Field;
double q = atof(argv[2]);
Field F(q);
SparseMatrix<Field> B (F);
B.read(input);
cout << "B is " << B.rowdim() << " by " << B.coldim() << endl;
if (B.rowdim() <= 20 && B.coldim() <= 20) B.write(cout) << endl;
// using Sparse Elimination
SE.strategy(Specifier::PIVOT_NONE);
Field::Element d;
det (d, B, SE);
if (B.rowdim() <= 20 && B.coldim() <= 20)
B.write(cout) << endl;
F.write(cout << "Determinant is ", d) << endl;
// using Sparse Elimination with reordering
SE.strategy(Specifier::PIVOT_LINEAR);
detin (d, B, SE);
if (B.rowdim() <= 20 && B.coldim() <= 20)
B.write(cout) << endl;
F.write(cout << "Determinant is ", d) << endl;
}
return 0;
}
// Local Variables:
// mode: C++
// tab-width: 8
// indent-tabs-mode: nil
// c-basic-offset: 8
// End:
// vim:sts=8:sw=8:ts=8:noet:sr:cino=>s,f0,{0,g0,(0,\:0,t0,+0,=s