awdiag.h

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/////////////////////////////////////////////////////////////////////////////
///
/// \file
///
/// Alexander-Whitney diagonal of a chain.
///
/////////////////////////////////////////////////////////////////////////////

// Copyright (C) 2009-2016 by Pawel Pilarczyk.
//
// This file is part of my research software package. This 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 <http://www.gnu.org/licenses/>.

// Started on March 24, 2009. Last revision: April 12, 2013.


#ifndef _CHAINCON_AWDIAG_H_
#define _CHAINCON_AWDIAG_H_


// include some standard C++ header files
#include <istream>
#include <ostream>

// include selected header files from the CHomP library
#include "chomp/system/config.h"

// include relevant local header files
#include "chaincon/combtensor.h"
#include "chaincon/tensor.h"


// --------------------------------------------------
// ------------------ AW diagonal -------------------
// --------------------------------------------------

/// Computes the Alexander-Whitney diagonal of a chain,
/// using the procedure defined for individual cells.
template <class CellT>
inline void AWdiagonal (const tCombChain<CellT> &ch,
        tCombTensor<CellT,CellT> &t)
{
        int_t size = ch. size ();
        for (int_t n = 0; n < size; ++ n)
                AWdiagonal (ch. getCell (n), t);
        return;
} /* AWdiagonal */

/// Computes the Alexander-Whitney diagonal of a chain,
/// using the procedure defined for individual cells.
template <class CellT, class CoefT>
inline void AWdiagonal (const tChain<CellT,CoefT> &ch,
        tTensor<CellT,CellT,CoefT> &t)
{
        int_t size = ch. size ();
        for (int_t n = 0; n < size; ++ n)
        {
                if (ch. getCoef (n) == 1)
                {
                        AWdiagonal (ch. getCell (n), t);
                }
                else
                {
                        tTensor<CellT,CellT,CoefT> tmp;
                        AWdiagonal (ch. getCell (n), tmp);
                        tmp *= ch. getCoef (n);
                        t += tmp;
                }
        }
        return;
} /* AWdiagonal */


#endif // _CHAINCON_AWDIAG_H_