main.cpp

/*
** EPITECH PROJECT, 2018
** groundhog
** File description:
** main.cpp
*/

#include <string>
#include <iostream>
#include <vector>
#include <cmath>

void print_help(void)
{
    std::cout << "SYNOPSIS" << std::endl;
    std::cout << "\t./groundhog period" << std::endl << std::endl;
    std::cout << "DESCRIPTION" << std::endl;
    std::cout << "\tperiod\tthe number of days defining a period" << std::endl;
}

double average(const std::vector<float> &indexes, const int period)
{
    unsigned long i;
    double avg = 0;

    if (indexes.empty())
        return 0;
    if (indexes.size() == 1)
        return indexes[0];
    for (i = 0; i < ((indexes.size() > period) ? period : indexes.size()); i++) {
        avg += indexes[i];
    }
    avg /= i;
    return avg;
}

double deviation(const std::vector<float> &indexes, const int period)
{
    unsigned long i;
    double dev = 0;
    double avg = average(indexes, period);

    if (indexes.empty())
        return 0;
    if (indexes.size() == 1)
        return 0;
    for (i = 0; i < ((indexes.size() > period) ? period : indexes.size()); i++) {
        dev += pow(indexes[i] - avg, 2);
    }
    dev /= i;
    return dev;
}

int main(int ac, char **av)
{
    std::vector<float> dataList = {};
    int period;

    if (ac != 2) {
        print_help();
        return 84;
    }
    try {
        period = std::stoi(av[1]);
    } catch (std::invalid_argument &e) {
        print_help();
        return 84;
    }
    for (std::string line; getline(std::cin, line);) {
        try {
            float num = stof(line);
            dataList.insert(dataList.begin(), num);
            std::cout << average(dataList, period) << ", " << deviation(dataList, period) << std::endl;
            if (dataList.size() > period)
                dataList.pop_back();
        } catch (std::invalid_argument &e) {
            return 84;
        }
    }
    return 0;
}