convenience.h

#include <utility>  // std::pair
#include <cmath>
#include <numeric>

std::pair<double, char> SIConvert(double v){
    std::pair<double, char> c(v,' ');
    int mag = log10(v);
    if(mag < -12){
        c.first *= 1e15;
        c.second = 'f';
    } else if(mag < -9){
        c.first *= 1e12;
        c.second = 'p';
    } else if(mag < -6){
        c.first *= 1e9;
        c.second = 'n';
    } else if(mag < -3){
        c.first *= 1e6;
        c.second = 'u';
    } else if(mag < 0){
        c.first *= 1e3;
        c.second = 'm';
    } else if(mag < 3){
    } else if(mag < 6){
        c.first *= 1e3;
        c.second = 'k';
    } else if(mag < 9){
        c.first *= 1e6;
        c.second = 'M';
    } else if(mag < 12){
        c.first *= 1e9;
        c.second = 'G';
    } else if(mag < 15){
        c.first *= 1e6;
        c.second = 'T';
    }
    return c;
}

std::pair<double,double> stats(std::vector<double> v){
   double sum = std::accumulate(v.begin(), v.end(), 0.0);
   double mean = sum / v.size();
 
   double sq_sum = std::inner_product(v.begin(), v.end(), v.begin(), 0.0);
   double stdev = std::sqrt(sq_sum / v.size() - mean * mean);
   return std::pair<double,double>(mean, stdev);
}