linbox
examples/rank.C

Rank of sparse matrix over Z or Zp.

/*
* examples/rank.C
*
* Copyright (C) 2005, 2010 D. Saunders, 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 <sstream>
#include <givaro/givrational.h>
#include <linbox/field/gf2.h>
#include <linbox/blackbox/zero-one.h>
#include <linbox/solutions/rank.h>
#include <linbox/util/matrix-stream.h>
#define SP_STOR SparseMatrixFormat::SparseSeq
// #define SP_STOR SparseMatrixFormat::COO
// #define SP_STOR SparseMatrixFormat::CSR
// #define SP_STOR SparseMatrixFormat::ELL
// #define SP_STOR SparseMatrixFormat::ELL_R
using namespace LinBox;
int main (int argc, char **argv)
{
commentator().setMaxDetailLevel (-1);
commentator().setMaxDepth (-1);
commentator().setReportStream (std::cerr);
if (argc < 2 || argc > 3) {
std::cerr << "Usage: rank <matrix-file-in-supported-format> [<p>]" << std::endl;
return -1;
}
std::ifstream input (argv[1]);
if (!input) {
std::cerr << "Error opening matrix file: " << argv[1] << std::endl;
return -1;
}
long unsigned int r;
Givaro::QField<Givaro::Rational> ZZ;
LinBox::Timer tim ; tim.clear() ; tim.start();
SparseMatrix<Givaro::QField<Givaro::Rational>, SP_STOR> A ( ms );
// SparseMatrix<Givaro::ZRing<Givaro::Rational>, SparseMatrixFormat::CSR> A ( ms );
tim.stop();
std::cout << "matrix is " << A.rowdim() << " by " << A.coldim() << " (" << tim << ")" << std::endl;
tim.clear() ; tim.start();
if (argc == 2) { // rank over the rational numbers.
/* We could pick a random prime and work mod that prime, But
* the point here is that the rank function in solutions/
* handles that issue. Our matrix here is an integer or
* rational matrix and our concept is that we are getting the
* rank of that matrix by some blackbox magic inside linbox.
*/
// A.write(std::cout) << std::endl;;
LinBox::rank (r, A);
}
if (argc == 3) { // rank mod a prime
#if 0
// for prime greater than wordsize:
integer q (argv[2]);
typedef Givaro::Modular<integer> Field;
#endif
#if 0
//to use doubles, prime < 2^{23}
double q = atof(argv[2]);
typedef Givaro::Modular<double> Field;
#endif
//to use ints, prime < 2^{31}
uint32_t q = atoi(argv[2]);
if (q == 0) {
std::cerr << "second argument should be a non-zero integer or missing\n";
return -1;
}
typedef Givaro::Modular<int32_t> Field;
Field F(q);
if (q > F.maxCardinality()) {
std::cerr << "your number is too big for this field" << std::endl;
return -1 ;
}
SparseMatrix<Field, SP_STOR > B (F, A.rowdim(), A.coldim());// modular image of A
MatrixHom::map(B, A);
std::cout << "matrix is " << B.rowdim() << " by " << B.coldim() << std::endl;
//if (B.rowdim() <= 20 && B.coldim() <= 20) B.write(std::cout) << std::endl;
// Using the adaptive LinBox Solution
// using BlackBoxes
#if 0 /* too bad */
MBB.certificate(true);
Linbox::rank(r, B, MBB);
#endif
// using in place Sparse Elimination with linear pivoting
#if 0 /* too bad */
SE.strategy(Specifier::PIVOT_LINEAR);
rankin (r, B, SE);
if (B.rowdim() <= 20 && B.coldim() <= 20) B.write(std::cout) << std::endl;
#endif
}
tim.stop();
std::cout << "Rank is " << r << " (" << tim << " )" << std::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