homology.h

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// This file copyright (C) 1997-2016 by Pawel Pilarczyk.
//
// This file is part of the "chomp" program. It is free software;
// you can redistribute it and/or modify it under the terms of the GNU
// General Public License as published by the Free Software Foundation,
// either version 3 of the License, or (at your option) any later version.
//
// This software 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 General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this software; see the file "license.txt". If not,
// please, see <https://www.gnu.org/licenses/>.
 
// Started on March 19, 2006. Last revision: July 27, 2007.
 
 
#ifndef _CAPD_HOMENGIN_HOMOLOGY_H_ 
#define _CAPD_HOMENGIN_HOMOLOGY_H_ 
 
#include <string>
#include <cstring>
#include "capd/homengin/engines.h"
 
 
inline void ComputeBettiNumbers (const void *buffer, int *sizes, int dim,
        int *result, const char *engine = 0, const int *wrapping = 0,
        bool quiet = false)
{
        using namespace chomp::homology;
        // turn off screen output if requested to
        bool soutput = sout. show;
        bool coutput = scon. show;
        if (quiet)
        {
                sout. show = false;
                scon. show = false;
                fcout. turnOff ();
        }
        else
                fcout. turnOn ();
 
        // create a corresponding set of cubes
        chomp::homengin::cubitmap X (reinterpret_cast<const char *> (buffer),
                sizes, dim);
 
        // set the space wrapping
        if (wrapping)
                X. setwrapping (wrapping, dim);
 
        // find the best engine to use for the homology computation
        const chomp::homengin::engine *e;
        if (!engine)
                e = chomp::homengin::engine::find (&X);
 
        // another possibility: find the engine with the given name
        else
                e = chomp::homengin::engine::find (engine);
 
        // compute the homology of the set of cubes
        chomp::homengin::algstruct<chomp::homology::integer> hom;
        e -> homology (X, hom);
        sout << "The computed homology is " << hom << ".\n";
 
        // fill in the resulting table of Betti numbers
        int levels = hom. countLevels ();
        for (int i = 0; i <= dim; ++ i)
                result [i] = (i < levels) ? hom. getBetti (i) : 0;
 
        // restore the message settings
        chomp::homology::sout. show = soutput;
        chomp::homology::scon. show = coutput;
        return;
} /* ComputeBettiNumbers */
 
 
// *** temporarily ***
#include "capd/homengin/cubiset.h"
 
 
#endif // _CAPD_HOMENGIN_HOMOLOGY_H_