d1_square and d2_square are the combined mean deviation .
float d1_square = ( mean1 - combinedMean ) * ( mean1 - combinedMean ) ; float d2_square = ( mean2 - combinedMean ) * ( mean2 - combinedMean ) ; cout << " d1 ▁ square : ▁ " << d1_square << " ▁ d2 _ square : ▁ " << d2_square << endl ;