Exemple #1
0
  void subtractMultipleTo(DMat<RT>& C, 
                          const DMat<RT>& A, 
                          const DMat<RT>& B)
  // C = C - A*B
  {
    typedef typename RT::ElementType ElementType;
    typedef typename DMat<RT>::ConstIterator ConstIterator;
    
    M2_ASSERT(A.numColumns() == B.numRows());
    M2_ASSERT(A.numRows() == C.numRows());
    M2_ASSERT(B.numColumns() == C.numColumns());

    ElementType* result = C.array();

    ElementType tmp;
    A.ring().init(tmp);
    // WARNING: this routine expects the result matrix to be in ROW MAJOR ORDER
    for (size_t i = 0; i<A.numRows(); i++)
      for (size_t j = 0; j<B.numColumns(); j++)
        {
          ConstIterator i1 = A.rowBegin(i);
          ConstIterator iend = A.rowEnd(i);
          ConstIterator j1 = B.columnBegin(j);
          
          while (i1 != iend)
            {
              A.ring().mult(tmp, *i1, *j1);
              A.ring().subtract(*result, *result, tmp);
              ++i1;
              ++j1;
            }
          result++;
        }
    A.ring().clear(tmp);
  }
Exemple #2
0
  void mult(const DMat<RT>& A, 
            const DMat<RT>& B, 
            DMat<RT>& result_product)
  {
    //printf("entering dmat mult\n");
    typedef typename RT::ElementType ElementType;
    typedef typename DMat<RT>::ConstIterator ConstIterator;
    
    M2_ASSERT(A.numColumns() == B.numRows());
    M2_ASSERT(A.numRows() == result_product.numRows());
    M2_ASSERT(B.numColumns() == result_product.numColumns());

    ElementType* result = result_product.array();

    ElementType tmp;
    A.ring().init(tmp);
    // WARNING: this routine expects the result matrix to be in ROW MAJOR ORDER
    for (size_t i = 0; i<A.numRows(); i++)
      for (size_t j = 0; j<B.numColumns(); j++)
        {
          ConstIterator i1 = A.rowBegin(i);
          ConstIterator iend = A.rowEnd(i);
          ConstIterator j1 = B.columnBegin(j);
          
          while (i1 != iend)
            {
              A.ring().mult(tmp, *i1, *j1);
              A.ring().add(*result, *result, tmp);
              ++i1;
              ++j1;
            }
          result++;
        }
    A.ring().clear(tmp);
  }