CuboidPyramidalMatrix.h

/*
 * CuboidPyramidalMatrix.h
 *
 *  Created on: Dec 11, 2014
 *      Author: uwe
 */
 
#ifndef CUBOIDPYRAMIDALMATRIX_H_
#define CUBOIDPYRAMIDALMATRIX_H_
 
#include "utils/mardyn_assert.h"
#include <cstdlib>
 
namespace bhfmm {
 
class CuboidPyramidalMatrix {
 
public:
    CuboidPyramidalMatrix() : _totalNumEntries(0), _numSlices(0), _entries(NULL) {}
 
    CuboidPyramidalMatrix(unsigned N, bool clean = false) :
            _totalNumEntries(N*(N+1)*(4*N-1)/6), _numSlices(N) {
        if (N != 0) {
            _entries = new double[_totalNumEntries];
        } else {
            _entries = NULL;
        }
        if (clean) clear();
    }
 
    CuboidPyramidalMatrix(const CuboidPyramidalMatrix& c) :
            _totalNumEntries(c._totalNumEntries), _numSlices(c._numSlices) {
 
        _entries = new double[_totalNumEntries];
        std::copy(c._entries, c._entries + c._totalNumEntries, _entries);
    }
 
    /* Assignment using copy-and-swap idiom */
    CuboidPyramidalMatrix& operator=(CuboidPyramidalMatrix rhs) {
        std::swap(_totalNumEntries, rhs._totalNumEntries);
        std::swap(_numSlices, rhs._numSlices);
        std::swap(_entries, rhs._entries);
        return *this;
    }
 
    ~~CuboidPyramidalMatrix() {if (_entries != NULL) delete[] _entries;}
 
    void clear() { for (unsigned i = 0; i < _totalNumEntries; ++i) _entries[i] = 0.0; }
 
    unsigned get_num_entries() const {return _totalNumEntries;}
 
    inline double & access(unsigned i, unsigned j, int k) {return _entries[index(i,j,k)];}
    inline const double& access_const(unsigned i, unsigned j, int k) const {return _entries[index(i,j,k)];}
    inline double & access_seq(unsigned i) {return _entries[i];}
    inline double access_seq_const(unsigned i) const {return _entries[i];}
 
    inline unsigned index(unsigned i, unsigned j, int k) const {
      mardyn_assert(i <= _numSlices);
      mardyn_assert(j <= i);
      mardyn_assert(static_cast<unsigned>(abs(k))<= i);
      return i*(i+1)*(4*i-1)/6 + (2*i + 1)*j + i + k;  // valid for i < 1024
 
      /* i*(i+1)*(4*i-1)/6  : select slice.
       * + (2*i + 1)*j      : select row
       * + i + k            : select column. k is signed -> start at the middle column i */
    }
 
private:
 
    unsigned _totalNumEntries;
    unsigned _numSlices;
 
    double* _entries;
};
 
} /* namespace bhfmm */
 
 
 
 
#endif /* CUBOIDPYRAMIDALMATRIX_H_ */