Digits

#include <iostream>
#include <vector>
#include <ctime>   // both this and the next header are needed for
#include <cstdlib> // rand() to randomly generate numbers
#include <cmath> // sqrt

using namespace std;

// calculate + print mean
void calcMean(const vector<double> &data)
{
    double sum = 0.0;
    for (size_t i = 0; i < data.size(); ++i)
    {
        sum += data[i];
    }
    cout << "Mean: " << sum / data.size() << endl;
}

// calc + print lowest
void findLo(const vector<double> &negative)
{
    double lowest = 0;
    for (size_t i = 0; i < negative.size(); ++i)
    {
        if (lowest > negative[i])
        { lowest = negative[i]; }
    }
    cout << "Lowest value: " << lowest << endl;
}

// calc + print lowest
void findHi(const vector<double> &positive)
{
    double highest = 0;
    for (size_t i = 0; i < positive.size(); ++i)
    {
        if (highest < positive[i])
        { highest = positive[i]; }
    }
    cout << "Highest value: " << highest << endl;
}

// print the list of both negative and positive numbers
void showVal(const vector<double> &positive,
             const vector<double> &negative)
{
    cout << "List of positive numbers: ";
    for (size_t i = 0; i < positive.size(); ++i)
    {
        cout << positive[i];
        if (i < (positive.size() - 1) ) // no ending comma
        { cout << ", "; }
    }

    cout << "\nList of negative numbers: ";
    for (size_t i = 0; i < negative.size(); ++i)
    {
        cout << negative[i];
        if (i < (negative.size() - 1) )
        { cout << ", "; }
    }
}

double split(const vector<double> &data)
{
    vector <double> positive;
    vector <double> negative;
    int j = 0; // iterate inner

    // add to pos/neg vector depending on value of data[i]
    for (size_t i = 0; i < data.size(); ++i)
    {

        if (data[i] >= 0)
        {
            positive.push_back(data[i]);
            j++;

        } else if (data[i] < 0)
        {
            negative.push_back(data[i]);
            j++;
        }
    }

    // debugging; output pos/neg vectors
/*    for (size_t vC = 0; vC < positive.size(); ++vC)
    {
        cout << positive[vC] << endl;
    }

    for (size_t vC = 0; vC < negative.size(); ++vC)
    {
        cout << negative[vC] << endl;
    }*/

    // "return" the 2 vectors to the needed functions
    findLo(negative);
    findHi(positive);
    showVal(positive, negative);

    return 0;
}

// calculate std deviation
double calculateSD(const vector<double> &data)
{
    // calculate sum of data
    double sum = 0.0;
    for (size_t i = 0; i < data.size(); ++i)
        sum += data[i];

    // calculate average
    double mean = sum / data.size();

    // calculate and return the standard deviation
    double standardDeviation = 0.0;
    for (size_t i = 0; i < data.size(); ++i)
        standardDeviation += (data[i] - mean) * (data[i] - mean);
    return sqrt(standardDeviation / data.size());
}



int main()
{
    // vector with minimum 30 values
    vector <double> data (30);

    // seed rand() with time
    srand(static_cast<unsigned int>(time(nullptr)));

    // fill vector with neg/pos num
    for (size_t i = 0; i < data.size(); ++i)
    {
        data[i] = rand() - (RAND_MAX / 2);
        //debnugginbg // cout << data[i] << endl;
    }
    // cout << "rand end"; yes this also dbunug

    cout << "Standard Deviation: " << calculateSD(data) << endl;
    calcMean(data);
    split(data);

}