Finding average of inputs using vector

[Toddinator716]

In a loop, ask the user for integers
If the user enters -1, end user input
Use an input validation loop to make sure the user input is 2 or greater Append the validated integer to the vector
Use the push_back() vector member function
Calculate and display the resulting arithmetic mean (average) of the vector WITH the new integer
Use the size() member function
If the mean is NOT a whole number:
Display a message rejecting the integer and remove the integer from the vector
Use the pop_back() member function
If the mean is a whole number:
Display a message accepting the integer and keep the integer in the vector
Once the user is done (user enters -1), calculate and display the mean of the first one element, first two
elements, and so on, until the mean of the entire vector is calculated and displayed
o Each mean should be a whole number


I'm trying to write a program for this, however I'm having a lot of trouble. I've tried it about 50 different ways. any suggestions?

I'm particularly having trouble checking whether or not the average is a whole integer (it's a double)

#include <iostream>
#include<vector>
#include <iomanip>
#include<cmath>
using namespace std;


int main() {


    double average = 0;
    double sum =0;
    double counter;

    vector<double>input;
    vector<double>sum1;
    vector<double>avgsize;
    vector<int>size;
    vector<double>numbers;

    vector<double>averagevector;

    counter = 0;
    do {
        cout<<"Please enter an integer (2 or greater, -1 to finish):";
        cin>>input[counter];
        if (input[counter] >= 2)
        {
            cout<<showpoint<<setprecision(5);
            numbers.push_back(input[counter]);
            sum = sum + input[counter];
            sum1.push_back(sum);

            cout<<"counter is "<<counter<<" \n";
            average = sum1[counter] / numbers.size();
            averagevector.push_back(average);

            cout << "The new arithmetic mean is " << averagevector[counter] << ".\n";
            counter++;


            if (fmod(averagevector[counter],1) != 0)
            {
                counter--;
                cout<<"Sorry, your input was rejected and will be removed! \n";
                numbers.pop_back();
                averagevector.pop_back();
                sum1.pop_back();
            } else{ cout<< "Your input has been accepted! fmod"<<endl;}
        }

        else if (input[counter] < 2 && input[counter] != -1)
        {
            cout << "That is not a valid number! Please try again." << endl;
            numbers.pop_back();
        }

    } while (input[counter] != -1);
    int limit;

    limit = numbers.size();
    cout<<"\nVector Elements:\n";
    for(int i=0; i < limit; ++i)
    {
        cout<<"numbers["<<i<<"] = "<<numbers[i]<<"\n";
    }
    cout<<"\n";
    for(int j=0; j < limit; ++j)
    {
        cout<<"Mean of the first "<<(j + 1)<<" element(s) : "<<averagevector[j]<<"\n";
    }
    cout<<"goodbye"<<endl;
    return 0;
}

[jonnin]

I'm particularly having trouble checking whether or not the average is a whole integer (it's a double)

if this is an absolute condition or you KNOW the values are small enough to always fit clean as a double, you can do the fairly simple check of
if( (int)(doublevar) == intvar)
but that is not a great approach general purpose, its usually better to check with something a little smarter
eg
if( abs(doublevar - intvar) < 0.00000001)
or something like that. You can get the exact values if you want to research it, or wing it, since its homework, is probably good enough?

[Toddinator716]

yes good call, this fixed it
if (fmod(mean,1) >= 0.001)
after rewriting almost from scratch I've perfected it

#include <iostream>
#include<vector>
#include<cmath>
using namespace std;

int main()
{
    double mean;
    double input;
    double sum;

    vector<double>numbers;
    vector<double>average_vector;

    do {
        cout<<"Please enter an integer (2 or greater, -1 to finish):";
        cin>>input;
        if (input >= 2)
        {
            numbers.push_back(input);
            sum = sum + input;
            mean = sum/numbers.size();
            average_vector.push_back(mean);
            cout << "The new arithmetic mean is " << mean <<"\n";

            if (fmod(mean,1) >= 0.001)
            {
                cout<<"Sorry, your input was rejected and will be removed! \n\n";
                numbers.pop_back();
                average_vector.pop_back();
                sum = sum - input;

            } else{ cout<< "Your input has been accepted!\n"<<endl;}
        }

        else if (input < 2 && input != -1)
        {
            cout << "\nThat is not a valid number! Please try again." << endl;
        }

    } while (input!= -1);
    int limit;

    limit = numbers.size();
    cout<<"\nVector Elements:\n";
    for(int i=0; i < limit; ++i)
    {
        cout<<"numbers["<<i<<"] = "<<numbers[i]<<"\n";
    }
    cout<<"\n";
    for(int j=0; j < limit; ++j)
    {
        cout<<"Mean of the first "<<(j + 1)<<" element(s) : "<<average_vector[j]<<"\n";
    }
    return 0;
}

[Toddinator716]

here's another program I wrote tonight that correlates with these concepts

#include <iostream>
#include<vector>
#include<iomanip>
using namespace std;

int main()
{
    vector<int>Home_score;
    vector<int>Away_score;
    int quarter =1;
    int width = 5;
    int homescore =0;
    int awayscore =0;
    int awaytotal=0;
    int hometotal=0;

        while(quarter<=4 || hometotal == awaytotal)
        {
            if(quarter>4 && hometotal == awaytotal)
            {
                cout<<"It's a tie! Let's play another quarter.\n";
            }
            cout << quarter << "Q away team score: \n";
            cout<<"Please enter a number (0 or greater): ";
            cin >> awayscore;
            while (awayscore <= 0)
            {
                cout<<"That is not a valid number! Please try again.\n";
                cout<<"Please enter a number (0 or greater): ";
                cin>>awayscore;
            }
            Away_score.push_back(awayscore);
            awaytotal = awaytotal + awayscore;
            cout << quarter << "Q home team score: \n";
            cout<<"Please enter a number (0 or greater): ";
            cin >> homescore;
            while (homescore <= 0)
            {
                cout<<"That is not a valid number! Please try again.\n";
                cout<<"Please enter a number (0 or greater): ";
                cin>>homescore;
            }
            Home_score.push_back(homescore);
            hometotal = hometotal + homescore;
            quarter++;
        }
        cout<<endl;
        int counter;
        counter = 1;
        cout<<setw(width)<<"";
        do
        {
            cout<<setw(width-1)<<counter<<"Q";
            counter++;
        }while(counter < quarter);
    cout<<setw(width+2)<<"TOTAL\n";
    cout<<setw(width)<<"AWAY";
    for (int i = 0; i < Away_score.size(); i++)
    {
        cout << setw(width)<<Away_score[ i ];
    }
    cout<<setw(width+1)<<awaytotal<<"\n";
    cout<<setw(width)<<"HOME";
    for (int j = 0; j < Home_score.size(); j++)
    {
        cout << setw(width)<<Home_score[ j ];
    }
    cout<<setw(width+1)<<hometotal<<"\n";
    return 0;
}