code: public static void add(final DMatrixD1 a , final DMatrixD1 b , final DMatrixD1 c )
      {
          if( a.numCols != b.numCols || a.numRows != b.numRows ) {
              throw new MatrixDimensionException("The matrices are not all the same dimension.");
          }
  
          c.reshape(a.numRows,a.numCols);
  
          final int length = a.getNumElements();
  
          for( int i = 0; i < length; i++ ) {
              c.set(i, a.get(i) + b.get(i));
          }
      }
docs: <p>Performs the following operation:<br>
  <br>
  c = a + b <br>
  c<sub>ij</sub> = a<sub>ij</sub> + b<sub>ij</sub> <br>
  </p>
  
  <p>
  Matrix C can be the same instance as Matrix A and/or B.
  </p>
  
  @param a A Matrix. Not modified.
  @param b A Matrix. Not modified.
  @param c A Matrix where the results are stored. Modified.