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#include <iostream>
#include <fstream>
#include <cmath>
#include "stdDevFns.h"
using namespace std;
// Definition of the function calcStdDev ()
bool calcStdDev (double inputArray [], int n, double & dev, double & avg)
{
bool success = true;
double total = 0.0, stdTotal=0.0;
if (n >= MinStudents && n <= MaxStudents)
{
success = true;
// calculate average grade
for (int i=0; i < n; i++)
total += inputArray [i];
avg = total / n;
// calculate standard deviation
for (int i=0; i < n; i++)
stdTotal += pow ((inputArray [i] - avg), 2);
dev = sqrt (stdTotal / (n-1));
}
else
success = false;
return success;
}
bool inputData (double gradeArray [], int &num)
{
bool worked = false, quit = false;
num = -1;
do
{
cout << "How many students do you have? " << endl;
cout << "Number must be between 2 and 25 (inclusive). Enter -1 to quit" << endl;
cin >> num;
if (num == -1)
quit = true;
else
quit = false;
} while ((num < MinStudents || num > MaxStudents) && !quit);
if (!quit)
{
// Use a for loop to enter data into the array
for (int i=0; i < num; i++)
{
cout << "Enter the grade for student " << i << ": ";
cin >> gradeArray [i];
}
worked = true;
}
return worked;
}
void outputData (double gradeArray [], int num)
{
cout << endl << "The grades for the class are : " << endl;
// Use a for loop to display the grades for the students
for (int i=0; i < num; i++)
{
cout << "Student " << i+1 << " has a grade of: " << gradeArray [i] << endl;
}
cout << endl;
}
bool inputFmFile (double gradeArray [], int &num)
{
bool worked = true, quit = false;
num = -1;
string inFileName;
ifstream inStr;
do
{
cout << "Enter name of file to read from: ";
cin >> inFileName;
inStr.open (inFileName.c_str());
if (inStr.fail())
{
cerr << "Error opening file. Try again." << endl;
inStr.clear();
worked = false;
}
else
worked = true;
} while (!worked);
inStr >> num;
if (num < MinStudents || num > MaxStudents)
{
quit = true;
worked = false;
}
else
quit = false;
if (!quit)
{
// Use a for loop to enter data into the array
for (int i=0; i < num; i++)
inStr >> gradeArray [i];
}
return worked;
}
void outputToFile (double gradeArray [], int num, double dev, double avg)
{
bool worked = false;
string outFileName;
ofstream outStr;
do
{
cout << "Enter name of file to write to: ";
cin >> outFileName;
outStr.open (outFileName.c_str());
if (outStr.fail())
{
cerr << "Error opening file. Try again." << endl;
outStr.clear();
worked = false;
}
else
worked = true;
} while (!worked);
outStr << num << endl;
// Use a for loop to display the grades for the students
for (int i=0; i < num; i++)
outStr << gradeArray [i] << endl;
outStr << dev << endl;
outStr << avg << endl;
}
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