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Class Averages

mymalibu8 (16)
Hello! A few days ago, I asked for help with a Class Average problem I was assigned, and have now worked through the code, but I can't get the right output! I'm going to copy and paste the directions, and an outline my professor gave us to help, then the code, so I hope someone can see where I've messed up. Thanks for the help!

Write a C++ program that will prompt the user for the name of a data file. This data file contains a list of student names (unknown number) in a class. The names are listed, one per line, in the following format: lastName firstName middleInitial and each part of the name is separated by a single space.

Each student has a data file which contains an unknown number of test scores. The name of each student’s data file is created by concatenating the student's first, middle initial and last name and then appending the suffix “.dat”. For example, if the student's name is Bobby B Baylor, the data file with this student's grades is called BobbieBBaylor.dat. If the input file cannot be found, then display "Cannot open " + filename.

Your program should open each student’s data file, read in the scores and calculate the student’s average. In addition to calculating the average for each student, the program should report the following statistics for the class : total number of students, average, maximum and minimum of the students' averages. If a student grade file is missing, then print "Cannot open " + student file name" and do not include the student's info in the class statistics.

Note: All statistics should be rounded to the nearest hundredth.

cout << fixed << setprecision(2);

Example:

Data File: students.dat

Flintstone Fred D

Rubble Barney E

Slate Walter A

FredDFlintstone.dat

85

88

92

86

77

32

BarneyERubble.dat

95

72

88

89

WalterASlate.dat

68

75

83

Sample Program Output #1 (bad file name):

Enter name of data file: stduent.dat

Cannot open stduent.dat


Sample Program Output #2 (all student files present):



Enter name of data file: students.dat<enter>

Student Statistics

Fred D. Flintstone : 76.67

Barney E. Rubble : 86.00

Walter A. Slate : 75.33

Class Statistics

Total Students : 3

Class Average : 79.23

Max Average : 86.00

Min Average : 75.33

Sample Program Output #3 (one student file missing):

Enter name of data file: students.dat

Student Statistics

Fred D. Flintstone : 76.67

Barney E. Rubble : 86.00

Walter A. Slate : Cannot open WalterASlate.dat

Class Statistics

Total Students : 2

Class Average : 80.40

Max Average : 86.00

Min Average : 76.67

And, here's the outline:
1. Initialize counters / accumulators
a. Number of students
b. Summary of class grades
c. Number of class grades
2. Prompt user for file name for the file with the list of student names
3. If file cannot be opened, then display “Cannot open “ message
4. Else
a. Loop through each line in input file until all students are processed
i. Format file name for student
ii. Print student name (no new line yet)
iii. Attempt to open student grade file
iv. If file cannot be opened, then display “cannot open” message
v. Else
1. Increment number of students
2. Reset student grade sum and counter to 0
3. Loop through student’s grades until all grades are processed
a. Sum the grades
b. Count the number of grades
4. Calculate student average
5. Display student average
6. Assign maximum average if 1st student or current average is higher
7. Assign minimum average if 1st student or current average is lower
8. Increment summary of class grades
9. Increment number of class grades
b. Calculate class average
i. If grade count > 0, calculate average ( sum of all grades / total number of grades)
c. Display the class statistics
i. If grade count = 0, display “No students”
ii. Else display the statistics
1. Number of students
2. Class average
3. Maximum average
4. Minimum average



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  #include <iostream> //for cout and cin
#include <iomanip> //for setprecision and setw
#include <fstream> //for ifstream and ofstream

//Initialize counters / accumulators
int numberOfStudents;
int summaryClassGrades;
int numberClassGrades;
int classAverage;
int totalGrade;
int maxAverage;
int minAverage;
int studentGrade;
int studentAverage;
int grade;
char lName [20];
char fName [20];
char mInitial [20];
const double HEADER_WIDTH = 25;


using namespace std;

int main()
{
    char fileName [50];
    ifstream inputFile;
    ifstream students;

    inputFile.open ("students.dat");
    //Prompt user for file name for the file with the list of student names
    cout << "Enter name of data file:" << endl;
    cin >> fileName;
    cout << fileName << endl;

    //If file cannot be opened, then display ÒCannot open Ò message
    if (inputFile.fail())
    {
        cout << "Cannot open student.dat" << endl;

    }
    else
    {   //Loop through each line in input file until all students are processed
        while (students >>  lName >> fName >> mInitial)
        {
         // format student grade file name
         ofstream studentsFileName;
         //Print Student Name
         cout << "Student Statistics";
         cout << "\t" << left << setw(HEADER_WIDTH)
              << studentsFileName << ": "
              << fixed << setw(2) << setprecision(2) << studentAverage
              << endl;

         //  open student grade  file
         students.open("studentsFileName.c_str()");
         if (students.fail())
         {  //If file cannot be opened, then display Òcannot openÓ message
             cout << "Cannot open " << studentsFileName << endl;
         }
         else
         {  //Increment number of students
             numberOfStudents++;
             //Reset student grade sum and counter to 0
             int gradeSum = 0;
             int gradeCount = 0;
             //Loop through student's grades until all grades are processed
                while (studentGrade)
                {
                 gradeSum++;
                 gradeCount++;

                }
             //Calculate student average
             studentAverage = studentGrade / numberClassGrades;
             //Display student average
             cout << studentAverage << endl;
             //Assign maximum average if 1st student or current
             //average is higher
             if (studentAverage >= 0)
             {
                 cout << maxAverage;
             }
             //Assign minimum average if 1st student or current average is lower
             else
             {
                 cout << minAverage;
             }
             //Increment summary of class grades
             summaryClassGrades++;
             //Increment number of class grades
             numberClassGrades++;
            }
      //Calculate class average
      classAverage =   summaryClassGrades / totalGrade;
      if (numberClassGrades > 0)
        {
            cout << classAverage;
        }
      if (numberClassGrades = 0)
      {
          cout << "No Students" << endl;
      }
      else
      {
          cout << "Total Students " << "\t :"
               << numberOfStudents << endl;
          cout << "Class Average " << "\t :"
               << classAverage << endl;
          cout << "Max Average" << "\t :"
               << maxAverage << endl;
          cout << "Min Average" << "\t :"
               << minAverage << endl;
               students.close();
      }
    }
    inputFile.close();
    return 0;
    }}
LB (13399)
What output is wrong?
mymalibu8 (16)
I can't get anything after entering the data file. So, nothing after line 43.
LB (13399)
If you add an output statement between lines 43 and 44, what happens?

Also, what are you trying to do with lines 47 and 51? It doesn't make sense to output a file stream into another stream.
mymalibu8 (16)
Can you explain what you mean by output statement?

And that's where I'm trying to create the individual files for each student, if that makes sense (see in the directions).
LB (13399)
mymalibu8 wrote:
Can you explain what you mean by output statement?
You know, that thing in the hello-world program that has the text "Hello, World!" and makes it show up on the screen? You did it on line 32 and in other places in your program ;)
mymalibu8 wrote:
And that's where I'm trying to create the individual files for each student, if that makes sense (see in the directions).
The file stream is created on line 47, but you never open any file for it to output to. Then on line 51 it looks like you're trying to take the unopened file stream and send it to std::cout, which makes no sense.
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