code: public T plus( T B ) {
          convertType.specify(this,B);
          T A = convertType.convert(this);
          B = convertType.convert(B);
  
          T ret = A.createMatrix(mat.getNumRows(),mat.getNumCols(), A.getType());
  
          A.ops.plus(A.mat,B.mat,ret.mat);
  
          return ret;
      }
docs: <p>
  Returns the result of matrix addition:<br>
  <br>
  c = a + b <br>
  <br>
  where c is the returned matrix, a is this matrix, and b is the passed in matrix.
  </p>
  
  @see CommonOps_DDRM#mult(DMatrix1Row, DMatrix1Row, DMatrix1Row)
  
  @param B m by n matrix. Not modified.
  
  @return The results of this operation.