Find combined mean and variance of two series | C ++ program to find combined mean and variance of two series . ; Function to find mean of series . ; Function to find the standard deviation of series . ; Function to find combined variance of two different series . ; mean1 and mean2 are the mean of two arrays . ; sd1 and sd2 are the standard deviation of two array . ; combinedMean is variable to store the combined mean of both array . ; d1_square and d2_square are the combined mean deviation . ; combinedVar is variable to store combined variance of both array . ; Driver function . ; Function call to combined mean .
#include <bits/stdc++.h> NEW_LINE using namespace std ; float mean ( int arr [ ] , int n ) { int sum = 0 ; for ( int i = 0 ; i < n ; i ++ ) sum = sum + arr [ i ] ; float mean = ( float ) sum / n ; return mean ; } float sd ( int arr [ ] , int n ) { float sum = 0 ; for ( int i = 0 ; i < n ; i ++ ) sum = sum + ( arr [ i ] - mean ( arr , n ) ) * ( arr [ i ] - mean ( arr , n ) ) ; float sdd = sum / n ; return sdd ; } float combinedVariance ( int arr1 [ ] , int arr2 [ ] , int n , int m ) { float mean1 = mean ( arr1 , n ) ; float mean2 = mean ( arr2 , m ) ; cout << " Mean1 : ▁ " << mean1 << " ▁ mean2 : ▁ " << mean2 << endl ; float sd1 = sd ( arr1 , n ) ; float sd2 = sd ( arr2 , m ) ; cout << " StandardDeviation1 : ▁ " << sd1 << " ▁ StandardDeviation2 : ▁ " << sd2 << endl ; float combinedMean = ( float ) ( n * mean1 + m * mean2 ) / ( n + m ) ; cout << " Combined ▁ Mean : ▁ " << combinedMean << endl ; float d1_square = ( mean1 - combinedMean ) * ( mean1 - combinedMean ) ; float d2_square = ( mean2 - combinedMean ) * ( mean2 - combinedMean ) ; cout << " d1 ▁ square : ▁ " << d1_square << " ▁ d2 _ square : ▁ " << d2_square << endl ; float combinedVar = ( n * ( sd1 + d1_square ) + m * ( sd2 + d2_square ) ) / ( n + m ) ; return combinedVar ; } int main ( ) { int arr1 [ ] = { 23 , 45 , 34 , 78 , 12 , 76 , 34 } ; int arr2 [ ] = { 65 , 67 , 34 , 23 , 45 } ; int n = sizeof ( arr1 ) / sizeof ( arr1 [ 0 ] ) ; int m = sizeof ( arr2 ) / sizeof ( arr2 [ 0 ] ) ; cout << " Combined ▁ Variance : ▁ " << combinedVariance ( arr1 , arr2 , n , m ) ; return 0 ; }