flower/include/matrix.hh

   1 /*
   2   matrix.hh -- declare Matrix
   3
   4   source file of the Flower Library
   5
   6   (c) 1996, 1997--1999 Han-Wen Nienhuys <hanwen@cs.uu.nl>
   7 */
   8
   9
  10 #ifndef MATRIX_HH
  11 #define MATRIX_HH
  12
  13 #include "full-storage.hh"
  14 #include "vector.hh"
  15 #include "offset.hh"
  16
  17 /**  a Real matrix.  This is a class for a nonsquare block of #Real#s.  The
  18     implementation of sparse matrices is done in the appropriate #smat#
  19     class. Matrix only does the mathematical actions (adding,
  20     multiplying, etc.)
  21
  22
  23     TODO
  24     implement ref counting?  */
  25
  26
  27 class Matrix {
  28   friend Matrix operator *(Matrix const &m1, Matrix const &m2);
  29
  30 protected:
  31   Full_storage *dat_;
  32   void set (Matrix_storage*);
  33 public:
  34   void OK() const { dat_->OK(); }
  35   void set_band ();
  36   int calc_band_i () const;
  37   int cols() const { return dat_->cols (); }
  38   int rows() const { return dat_->rows (); }
  39
  40   /**  return the size of a matrix.
  41     PRE
  42     the matrix needs to be square.
  43     */
  44   int dim() const;
  45
  46   /**
  47     the band size of the matrix.
  48     @ret
  49
  50     0 <= band_i() <= dim
  51     */
  52   int band_i() const;
  53
  54   /// set entries to r
  55   void fill (Real r);
  56
  57   /// set diagonal to d
  58   void set_diag (Real d);
  59
  60   void set_diag (Vector d);
  61   /// set unit matrix
  62   void unit() { set_diag (1.0); }
  63
  64   void operator+=(Matrix const &m);
  65   void operator-=(Matrix const &m);
  66   void operator*=(Real a);
  67   void operator/=(Real a) { (*this) *= 1/a; }
  68
  69   /**  add a row.
  70     add a row to the matrix before  row k
  71
  72     PRE
  73     v.dim() == cols ()
  74     0 <= k <= rows()
  75     */
  76   void insert_row (Vector v,int k);
  77   /** .
  78     delete a row from this matrix.
  79
  80     PRE
  81     0 <= k < rows();
  82     */
  83   void delete_row (int k) { dat_->delete_row (k); }
  84   void delete_column (int k) { dat_->delete_column (k); }
  85
  86   /**
  87     square n matrix, initialised to null
  88     */
  89   Matrix (int n);
  90
  91   /**
  92     n x m matrix, init to 0
  93     */
  94   Matrix (int n, int m);
  95   Matrix (Matrix const &m);
  96
  97   /// dyadic product: v * w.transpose
  98   Matrix (Vector v, Vector w);
  99   void operator=(Matrix const &m);
 100
 101   /// access an element
 102   Real operator()(int i,int j) const { return dat_->elem (i,j); }
 103
 104   /// access an element
 105   Real &operator()(int i, int j) { return dat_->elem (i,j); }
 106
 107   /// Matrix multiply with vec (from right)
 108   Vector operator *(Vector const &v) const;
 109
 110   /// set this to m1*m2.
 111   void set_product (Matrix const &m1, Matrix const &m2);
 112
 113   Vector left_multiply (Vector const &) const;
 114
 115   Matrix operator-() const;
 116
 117   /// transpose this.
 118   void transpose();
 119
 120   /// return a transposed copy.
 121   Matrix transposed() const ;
 122
 123   Real norm() const;
 124   /**  swap.
 125     PRE
 126     0 <= c1,c2 < cols()
 127     */
 128   void swap_columns (int c1, int c2);
 129
 130   /**  swap.
 131     PRE
 132     0 <= c1,c2 < rows()
 133     */
 134   void swap_rows (int c1, int c2);
 135
 136
 137   Vector row (int) const;
 138   Vector col (int) const;
 139
 140   String str () const;
 141   void print() const;
 142   ~Matrix ();
 143 };
 144
 145 inline Vector
 146 operator *(Vector &v, Matrix const & m) { return m.left_multiply (v); }
 147 Matrix operator *(Matrix const & m1,Matrix const &m2);
 148 Matrix operator /(Matrix const &m1,Real a);
 149 inline Matrix operator -(Matrix m1,const Matrix m2)
 150 {
 151   m1 -= m2;
 152   return m1;
 153 }
 154 inline Matrix operator +(Matrix m1,const Matrix m2)
 155 {
 156   m1 += m2;
 157   return m1;
 158 }
 159 #endif