/*
 * examples/sparseelimrank.C
 *
 * Copyright (C) 2017  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========
 */

/** \file examples/sparseelimrankgf2.C
 * @example  examples/sparseelimrankgf2.C
 \brief Gaussian elimination Rank of sparse matrix mod 2
 \ingroup examples
 */

#include <linbox/linbox-config.h>
#include <iostream>
#include <linbox/algorithms/gauss-gf2.h>
#include <linbox/solutions/det.h>

using namespace LinBox;

int main (int argc, char **argv) {
    
	if (argc <2) {	
        std::cerr << "Usage: sparseelimrankgf2 <matrix-file-in-sms-format>" << std::endl; 
        return -1; 
    }

	std::ifstream input (argv[1]);
	if (!input) { 
        std::cerr << "Error opening matrix file: " << argv[1] << std::endl; 
        return -1; 
    }

	LinBox::GF2::Element d;
    
    LinBox::ZeroOne<LinBox::GF2> A;
    A.read(input); // input in SMS format

    std::cout << "A is " << A.rowdim() << " by " << A.coldim()  << std::endl;
    if (A.rowdim() <= 20 && A.coldim() <= 20) A.write(std::cout) << std::endl;

        // using Sparse Elimination with linear pivoting
    GaussDomain<GF2> GD ( A.field() );
    GD.detin (d, A, Specifier::PIVOT_LINEAR);

    if (A.rowdim() <= 20 && A.coldim() <= 20) A.write(std::cout,Tag::FileFormat::Maple) << std::endl;

    A.field().write(std::cout << "Det is ", d) << " over GF2" << std::endl;

	return 0;
}

// vim:sts=4:sw=4:ts=4:noet:sr:cino=>s,f0,{0,g0,(0,:0,t0,+0,=s
// Local Variables:
// mode: C++
// tab-width: 4
// indent-tabs-mode: nil
// c-basic-offset: 4
// End: