cs-lab34/histogram.cpp

#include "histogram.h"
#include "histogram_internal.h"
#include <vector>
using std::vector;
void find_minmax(const vector<double>& numbers, double& min, double& max) {
    if (numbers.empty())
    {
        min = 0;
        max = 0;
        return;
    }
    max = numbers[0];
    min = numbers[0];
    for (double x : numbers) {
        if (x < min) min = x;
        else if (x > max) max = x;
    }
}

std::vector<size_t> make_histogram(const std::vector<double>& numbers, size_t bin_count) {
    std::vector<size_t> bins(bin_count, 0);

    double min, max;
    find_minmax(numbers, min, max);

    double bin_size = (max - min) / bin_count;

    for (double number : numbers) {
        bool found = false;
        for (size_t j = 0; (j < bin_count - 1) && !found; j++) {
            double lo = min + j * bin_size;
            double hi = min + (j + 1) * bin_size;
            if ((lo <= number) && (number < hi)) {
                bins[j]++;
                found = true;
            }
        }
        if (!found) {
            bins[bin_count - 1]++;
        }
    }

    return bins;
}