Dogcows Code - chaz/yoink/blob - src/stlplus/containers/matrix.tpp

   1 ////////////////////////////////////////////////////////////////////////////////
   2
   3 //   Author:    Andy Rushton
   4 //   Copyright: (c) Southampton University 1999-2004
   5 //              (c) Andy Rushton           2004-2009
   6 //   License:   BSD License, see ../docs/license.html
   7
   8 ////////////////////////////////////////////////////////////////////////////////
   9
  10 namespace stlplus
  11 {
  12
  13   ////////////////////////////////////////////////////////////////////////////////
  14
  15   template<typename T>
  16   matrix<T>::matrix(unsigned rows, unsigned cols, const T& fill) throw()
  17   {
  18     m_rows = 0;
  19     m_cols = 0;
  20     m_data = 0;
  21     resize(rows,cols,fill);
  22   }
  23
  24   template<typename T>
  25   matrix<T>::~matrix(void) throw()
  26   {
  27     for (unsigned row = 0; row < m_rows; row++)
  28       delete[] m_data[row];
  29     delete[] m_data;
  30   }
  31
  32   template<typename T>
  33   matrix<T>::matrix(const matrix<T>& r) throw()
  34   {
  35     m_rows = 0;
  36     m_cols = 0;
  37     m_data = 0;
  38     *this = r;
  39   }
  40
  41   template<typename T>
  42   matrix<T>& matrix<T>::operator =(const matrix<T>& right) throw()
  43   {
  44     // clear the old values
  45     for (unsigned row = 0; row < m_rows; row++)
  46       delete[] m_data[row];
  47     delete[] m_data;
  48     m_rows = 0;
  49     m_cols = 0;
  50     m_data = 0;
  51     // now reconstruct with the new
  52     resize(right.m_rows, right.m_cols);
  53     for (unsigned row = 0; row < m_rows; row++)
  54       for (unsigned col = 0; col < m_cols; col++)
  55         m_data[row][col] = right.m_data[row][col];
  56     return *this;
  57   }
  58
  59   template<typename T>
  60   void matrix<T>::resize(unsigned rows, unsigned cols, const T& fill) throw()
  61   {
  62     // a grid is an array of rows, where each row is an array of T
  63     // a zero-row or zero-column matrix has a null grid
  64     // TODO - make this exception-safe - new could throw here and that would cause a memory leak
  65     T** new_grid = 0;
  66     if (rows && cols)
  67     {
  68       new_grid = new T*[rows];
  69       for (unsigned row = 0; row < rows; row++)
  70       {
  71         new_grid[row] = new T[cols];
  72         // copy old items to the new grid but only within the bounds of the intersection of the old and new grids
  73         // fill the rest of the grid with the initial value
  74         for (unsigned col = 0; col < cols; col++)
  75           if (row < m_rows && col < m_cols)
  76             new_grid[row][col] = m_data[row][col];
  77           else
  78             new_grid[row][col] = fill;
  79       }
  80     }
  81     // destroy the old grid
  82     for (unsigned row = 0; row < m_rows; row++)
  83       delete[] m_data[row];
  84     delete[] m_data;
  85     // move the new data into the matrix
  86     m_data = new_grid;
  87     m_rows = rows;
  88     m_cols = cols;
  89   }
  90
  91   template<typename T>
  92   unsigned matrix<T>::rows(void) const throw()
  93   {
  94     return m_rows;
  95   }
  96
  97   template<typename T>
  98   unsigned matrix<T>::columns(void) const throw()
  99   {
 100     return m_cols;
 101   }
 102
 103   template<typename T>
 104   void matrix<T>::erase(const T& fill) throw()
 105   {
 106     for (unsigned row = 0; row < m_rows; row++)
 107       for (unsigned col = 0; col < m_cols; col++)
 108         insert(row,col,fill);
 109   }
 110
 111   template<typename T>
 112   void matrix<T>::erase(unsigned row, unsigned col, const T& fill) throw(std::out_of_range)
 113   {
 114     insert(row,col,fill);
 115   }
 116
 117   template<typename T>
 118   void matrix<T>::insert(unsigned row, unsigned col, const T& element) throw(std::out_of_range)
 119   {
 120     if (row >= m_rows) throw std::out_of_range("matrix::insert row");
 121     if (col >= m_cols) throw std::out_of_range("matrix::insert col");
 122     m_data[row][col] = element;
 123   }
 124
 125   template<typename T>
 126   const T& matrix<T>::item(unsigned row, unsigned col) const throw(std::out_of_range)
 127   {
 128     if (row >= m_rows) throw std::out_of_range("matrix::item row");
 129     if (col >= m_cols) throw std::out_of_range("matrix::item col");
 130     return m_data[row][col];
 131   }
 132
 133   template<typename T>
 134   T& matrix<T>::item(unsigned row, unsigned col) throw(std::out_of_range)
 135   {
 136     if (row >= m_rows) throw std::out_of_range("matrix::item row");
 137     if (col >= m_cols) throw std::out_of_range("matrix::item col");
 138     return m_data[row][col];
 139   }
 140
 141   template<typename T>
 142   const T& matrix<T>::operator()(unsigned row, unsigned col) const throw(std::out_of_range)
 143   {
 144     if (row >= m_rows) throw std::out_of_range("matrix::operator() row");
 145     if (col >= m_cols) throw std::out_of_range("matrix::operator() col");
 146     return m_data[row][col];
 147   }
 148
 149   template<typename T>
 150   T& matrix<T>::operator()(unsigned row, unsigned col) throw(std::out_of_range)
 151   {
 152     if (row >= m_rows) throw std::out_of_range("matrix::operator() row");
 153     if (col >= m_cols) throw std::out_of_range("matrix::operator() col");
 154     return m_data[row][col];
 155   }
 156
 157   template<typename T>
 158   void matrix<T>::fill(const T& item) throw()
 159   {
 160     erase(item);
 161   }
 162
 163   template<typename T>
 164   void matrix<T>::fill_column(unsigned col, const T& item) throw (std::out_of_range)
 165   {
 166     if (col >= m_cols) throw std::out_of_range("matrix::fill_column");
 167     for (unsigned row = 0; row < m_rows; row++)
 168       insert(row, col, item);
 169   }
 170
 171   template<typename T>
 172   void matrix<T>::fill_row(unsigned row, const T& item) throw (std::out_of_range)
 173   {
 174     if (row >= m_rows) throw std::out_of_range("matrix::fill_row");
 175     for (unsigned col = 0; col < m_cols; col++)
 176       insert(row, col, item);
 177   }
 178
 179   template<typename T>
 180   void matrix<T>::fill_leading_diagonal(const T& item) throw()
 181   {
 182     for (unsigned i = 0; i < m_cols && i < m_rows; i++)
 183       insert(i, i, item);
 184   }
 185
 186   template<typename T>
 187   void matrix<T>::fill_trailing_diagonal(const T& item) throw()
 188   {
 189     for (unsigned i = 0; i < m_cols && i < m_rows; i++)
 190       insert(i, m_cols-i-1, item);
 191   }
 192
 193   template<typename T>
 194   void matrix<T>::make_identity(const T& one, const T& zero) throw()
 195   {
 196     fill(zero);
 197     fill_leading_diagonal(one);
 198   }
 199
 200   template<typename T>
 201   void matrix<T>::transpose(void) throw()
 202   {
 203     // no gain in manipulating this, since building a new matrix is no less efficient
 204     matrix<T> transposed(columns(), rows());
 205     for (unsigned row = 0; row < rows(); row++)
 206       for (unsigned col = 0; col < columns(); col++)
 207         transposed.insert(col,row,item(row,col));
 208     // TODO - avoid an extra copy by swapping the member data here
 209     *this = transposed;
 210   }
 211
 212   ////////////////////////////////////////////////////////////////////////////////
 213
 214 } // end namespace stlplus
 215