code: public void apply(Matrix H, int column, int i1, int i2) {
          double temp = c * H.get(i1, column) + s * H.get(i2, column);
          H.set(i2, column, -s * H.get(i1, column) + c * H.get(i2, column));
          H.set(i1, column, temp);
      }
docs: Applies the Givens rotation to two elements in a matrix column
  
  @param H
  Matrix to apply to
  @param column
  Column index
  @param i1
  Row index of first element
  @param i2
  Row index of second element