Returns a Grid2DSquareCellDouble with values of grid2DSquareCellDouble
added with values from grid2DSquareCellDoubleToAdd (with row index between
startRowIndex, endRowIndex and column index between startColIndex,
endColIndex) multiplied by weight.
Returns a Grid2DSquareCellDouble with values of grid2DSquareCellDouble
added with values from grid2DSquareCellDoubleToAdd (with row index between
startRowIndex, endRowIndex and column index between startColIndex,
endColIndex) multiplied by weight.