#include <iostream>#include <utility>#include <string>#include <vector>#include "sample.h"using namespace std;// returns the square of a doubledouble square(double x) { return x * x;}// sample class member functions after this point// no. of elements in the sampleint sample::size() { return samples.size(); }// value at an element n, in the sampledouble sample::at(int n) { return samples.at(n); }// return the vector itselfconst vector<double> &sample::getdata() { return samples; }// sets the data vector itselfvoid sample::set_data(const vector<double> &v) { samples = v;}// returns the lowest value in a sorted sampledouble sample::minimum() { std::sort(samples.begin(), samples.end()); return samples.at(0);}// returns the highest value in a sorted sampledouble sample::maximum() { std::sort(samples.begin(), samples.end()); return samples.at(samples.size() - 1);}// returns the difference between the max and min valuesdouble sample::range() { return (maximum() - minimum()); }// returns halfway between the max and min valuesdouble sample::midrange() { return (maximum() + minimum()) / 2; }// returns the mean of the sampledouble sample::mean() { double total = sum_elements(); int total_elements = samples.size(); return total/total_elements;}// the variance of the sampledouble sample::variance() { // sum of x double sumx = sum_elements(); // sum of (x squared) double sumxsquared = 0; for (int i = 0; i <= (signed)samples.size() - 1; i++) sumxsquared += square(samples[i]); // no. of elements int n = (signed)samples.size(); return (sumxsquared - ((square(sumx))/n)) / n; }// the s.d. of the sampledouble sample::std_deviation() { return sqrt(variance());}// the median of the sample after sortingdouble sample::median() { std::sort(samples.begin(), samples.end()); bool n_is_odd = samples.size() % 2; // odd no. of elements if (n_is_odd) { cout << "odd no. elements\n"; return samples[((samples.size() + 1) / 2)]; } // even number of elements else { double j = samples[samples.size() / 2]; double k = samples[(samples.size() / 2) + 1]; return (j + k) / 2; } }// the sum of the value of the elements in the sampledouble sample::sum_elements() { double sumx = 0; for (int i = 0; i <= (signed)samples.size() - 1; i++) sumx += samples[i]; return sumx;}// independent functions after this point----------------------// operator for writing sampleostream& operator<<(ostream &s, sample p) { s << "<" << p.size() << ": "; for (int i = 0; i <= p.size() - 1; i++) s << p.at(i) << " "; s << ">";}istream& operator>>(istream &s, sample &p) { int x; double currdouble; char larrow, semicolon, rarrow; if ((s >> larrow) && (larrow == '<')) { if ((s >> x >> semicolon) && (semicolon == ':')) { vector<double> vi(x); for (int i = 0; i <= (signed)vi.size() - 1; i++) { s >> currdouble; vi[i] = currdouble; } if ((s >> rarrow) && (rarrow == '>')) { p = sample(vi); // cout << "Sample added.\n"; } } else s.setstate(ios::badbit); // read failed } return s;}