Question

This is the program that use to find the Mean (Average) and Median in C++.

#include <iostream>
#include <fstream>
#include <iomanip>
#include <cstdlib> // used by the exit() functiona

using namespace std;

int main(int argc, char* argv[])
{
// variables to control the disk file
ifstream infile;
char filename[200];
int recordCount = 0;
int recordsToSkip = 0;
// variables for fields of each record in the file
int AcctNo = 0;
char Name[100] = "";
double AcctBal = 0.0;
// varible used to determine the median
double median = 0.0;
double total = 0.0;
double mean = 0.0;
  

cout << "Enter the name of the data file: ";
cin >> filename;

// ---- PART 1, Count the number of records in the file
// Determine the mean when you know the record count and the total of all balances
infile.open("C:\\Users\\An\\Desktop\\Balances1.txt");
if (infile.fail())
{
cerr << "Unable to open --" << filename << "--, first pass" << endl;
exit(1);
}
while (!infile.eof()) // while not end of file
{
if (Name[0] = !0)// initialize to 0 to test for empty records/
{
total += AcctBal;
recordCount++;
}
Name[0] = 0;
infile >> AcctNo >> Name >> AcctBal;
}

infile.close();
cout << "There are " << recordCount << " records in " << filename << endl;
mean = total / recordCount;
cout << endl << "The mean value of the balance is " << setprecision(3) << fixed << mean << endl;

// ---- PART 2, Determine the number of records to skip
if (recordCount %2 == 1)
recordsToSkip = recordCount / 2; // Odd number of records
else
recordsToSkip = recordCount / 2 - 1; // Even number of records
cout << "recordsToSkip = " << recordsToSkip << endl;

// ---- PART 3, open the file, skip leading records, determine the median
infile.open("C:\\Users\\An\\Desktop\\Balances1.txt");
if (infile.fail())
{
cerr << "Unable to open --" << filename << "--, second pass" << endl;
exit(1);
}
while (recordsToSkip != 0)
{
infile >> AcctNo >> Name >> AcctBal;
recordsToSkip--;
}

infile >> AcctNo >> Name >> AcctBal;
if (recordCount % 2 == 1)
{
median = AcctBal;
}
else
{
median = AcctBal;
infile >> AcctNo >> Name >> AcctBal;
median = (median + AcctBal) / 2;
}
infile.close();

// Display the results
cout << endl << "The median of " << filename << " is " << setprecision(3) << fixed << median << endl << endl;
  
return 0;
}

However, when I use Excel to double check the result. Those outputs are different. I think I have mistakes some where in the program. I need some help from you. Thank you.

This is the .txt file for the Balances ( Balance 1 and Balance 2)

http://program-info.net/C++/downloads/C++MedianOfFile/Balances-1.txt

http://program-info.net/C++/downloads/C++MedianOfFile/Balances-2.txt

Answer 1

Please find your solution below and if doubt comment and do upvote.

CODE:

#include <iostream>
#include <fstream>
#include <iomanip>
#include <cstdlib> // used by the exit() functiona

using namespace std;

int main(int argc, char* argv[])
{
    // variables to control the disk file
    ifstream infile;
    char filename[200];
    int recordCount = 0;
    int recordsToSkip = 0;
    // variables for fields of each record in the file
    int AcctNo = 0;
    char Name[100] = "";
    //Name[0]=0;
    double AcctBal = 0.0;
    // varible used to determine the median
    double median = 0.0;
    double total = 0.0;
    double mean = 0.0;
    cout << "Enter the name of the data file: ";
    cin >> filename;
    
    // ---- PART 1, Count the number of records in the file
    // Determine the mean when you know the record count and the total of all balances
    infile.open("Balances1.txt");
    if (infile.fail())
    {
        cerr << "Unable to open --" << filename << "--, first pass" << endl;
        exit(1);
        
    }
    int i=1;
    infile >> AcctNo >> Name >> AcctBal;
    while (!infile.eof()) // while not end of file
    {
        //cout<<i++<<" "<<AcctNo <<" "<<Name<<" "<<AcctBal<<endl;
        if (Name[0] = !0)// initialize to 0 to test for empty records/
        {
            total += AcctBal;
            recordCount++;
            
        }
        Name[0] = 0;
        infile >> AcctNo >> Name >> AcctBal;
         //cout<<i++<<" "<<AcctNo <<" "<<Name<<" "<<AcctBal<<endl;
        
    }
    infile.close();
    cout << "There are " << recordCount << " records in " << filename << endl;
   // cout<<"Sum"<<total<<endl;
    mean = total / recordCount;
    cout << endl << "The mean value of the balance is " << setprecision(3) << fixed << mean << endl;
    // ---- PART 2, Determine the number of records to skip
    if (recordCount %2 == 1)
    recordsToSkip = recordCount / 2; // Odd number of records
    else
    recordsToSkip = recordCount / 2 - 1; // Even number of records
    cout << "recordsToSkip = " << recordsToSkip << endl;
    // ---- PART 3, open the file, skip leading records, determine the median
    infile.open("Balances1.txt");
    if (infile.fail())
    {
        cerr << "Unable to open --" << filename << "--, second pass" << endl;
        exit(1);
        
    }
    while (recordsToSkip != 0)
    {
        infile >> AcctNo >> Name >> AcctBal;
        recordsToSkip--;
        
    }
    infile >> AcctNo >> Name >> AcctBal;
    if (recordCount % 2 == 1)
    {
        median = AcctBal;
        
    }
    else
    {
        median = AcctBal;
        infile >> AcctNo >> Name >> AcctBal;
        median = (median + AcctBal) / 2;
        
    }
    infile.close();
    
    // Display the results
    cout << endl << "The median of " << filename << " is " << setprecision(3) << fixed << median << endl << endl;
  
return 0;
}

OUTPUT: