Mega Code Archive
Compute the sample standard deviation
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#include <algorithm>
#include <cmath>
#include <functional>
#include <iostream>
#include <list>
#include <numeric>
#include <vector>
using namespace std;
template <class T>
void print(T& c){
for( typename T::iterator i = c.begin(); i != c.end(); i++ ){
std::cout << *i << endl;
}
}
int main( )
{
const float a[] = { 1, 1.3, 1.5};
vector<float> data( a,a + sizeof( a ) / sizeof( a[0] ) );
print( data );
float mean = accumulate( data.begin(), data.end(), 0.0f )/ data.size();
cout << mean;
vector<float> zero_mean( data );
transform( zero_mean.begin(), zero_mean.end(), zero_mean.begin(),bind2nd( minus<float>(), mean ) );
float deviation = inner_product( zero_mean.begin(),zero_mean.end(), zero_mean.begin(), 0.0f );
deviation = sqrt( deviation / ( data.size() - 1 ) );
cout << deviation;
}
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