iterator.h

来自「高效的c++科学算法库」· C头文件 代码 · 共 88 行

/*                                                          -*- c++ -*-
 ******************************
 * Scientific Library (GNU Public Licence)
 *
 * Author: Laurent Deniau, [e-mail]
 *
 * $Id: iterator.h,v 1.1 1998/11/05 12:48:39 paubert Exp $
 *
 * Suggestions: [e-mail]
 * Bugs:   [e-mail]
 *
 * For more information, please see the sl++ Home Page:
 * http://wwwinfo.cern.ch/~ldeniau/sl.html
 *
 ******************************
 */

#ifndef SL_MATRIX_STRUCTURES_SYMMETRIC_ITERATOR_H
#define SL_MATRIX_STRUCTURES_SYMMETRIC_ITERATOR_H

#ifndef SL_MATRIX_STRUCTURES_SYMMETRIC_H
#error <sl/matrix/structures/symmetric/iterator.h> must be included via <sl/matrix/structures/symmetric.h>
#endif

#ifdef HAVE_NAMESPACE
namespace sl 
{
#endif

    class SymmetricIterator : public GeneralIterator {


      public:

        typedef Symmetric structure_t;


      private:

        Index
            map (Index const i, Index const j) const {
            return j<=i ? (i-MinIndex)*(i-MinIndex+1)/2+j : 
                (j-MinIndex)*(j-MinIndex+1)/2+i;
        }


      public:

            SymmetricIterator(structure_t const* structure,
                              Index const i =MinIndex, Index const j =MinIndex)
            : GeneralIterator(structure->rows(),structure->cols(),
                              i, j, map(i,j))
            {
                assert (  structure->rows() == structure->cols() );
            }


      public:

        void
            operator ++ () {
            if (++my_j > my_i) {
                my_j = MinIndex;
                if (++my_i > my_n) my_ok = false;
            }
            ++my_o;
        }

        void
            incRow() {
            if (++my_i > my_n) my_ok = false;
            else my_o += my_i-1;
        }

        void
            incCol() {
            if (++my_j > my_i) my_ok = false;
            else ++my_o;
        }
    };

#ifdef HAVE_NAMESPACE
}
#endif 

#endif
// SL_MATRIX_STRUCTURES_SYMMETRIC_ITERATOR_H