?? gradebook.cpp
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// Fig. 7.24: GradeBook.cpp
// Member-function definitions for class GradeBook that
// uses a two-dimensional array to store grades.
#include <iostream>
using std::cout;
using std::cin;
using std::endl;
using std::fixed;
#include <iomanip> // parameterized stream manipulators
using std::setprecision; // sets numeric output precision
using std::setw; // sets field width
// include definition of class GradeBook from GradeBook.h
#include "GradeBook.h"
// two-argument constructor initializes courseName and grades array
GradeBook::GradeBook( string name, const int gradesArray[][ tests ] )
{
setCourseName( name ); // initialize courseName
// copy grades from gradeArray to grades
for ( int student = 0; student < students; student++ )
for ( int test = 0; test < tests; test++ )
grades[ student ][ test ] = gradesArray[ student ][ test ];
} // end two-argument GradeBook constructor
// function to set the course name
void GradeBook::setCourseName( string name )
{
courseName = name; // store the course name
} // end function setCourseName
// function to retrieve the course name
string GradeBook::getCourseName()
{
return courseName;
} // end function getCourseName
// display a welcome message to the GradeBook user
void GradeBook::displayMessage()
{
// this statement calls getCourseName to get the
// name of the course this GradeBook represents
cout << "Welcome to the grade book for\n" << getCourseName() << "!"
<< endl;
} // end function displayMessage
// perform various operations on the data
void GradeBook::processGrades()
{
// output grades array
outputGrades();
// call functions getMinimum and getMaximum
cout << "\nLowest grade in the grade book is " << getMinimum()
<< "\nHighest grade in the grade book is " << getMaximum() << endl;
// output grade distribution chart of all grades on all tests
outputBarChart();
} // end function processGrades
// find minimum grade
int GradeBook::getMinimum()
{
int lowGrade = 100; // assume lowest grade is 100
// loop through rows of grades array
for ( int student = 0; student < students; student++ )
{
// loop through columns of current row
for ( int test = 0; test < tests; test++ )
{
// if current grade less than lowGrade, assign it to lowGrade
if ( grades[ student ][ test ] < lowGrade )
lowGrade = grades[ student ][ test ]; // new lowest grade
} // end inner for
} // end outer for
return lowGrade; // return lowest grade
} // end function getMinimum
// find maximum grade
int GradeBook::getMaximum()
{
int highGrade = 0; // assume highest grade is 0
// loop through rows of grades array
for ( int student = 0; student < students; student++ )
{
// loop through columns of current row
for ( int test = 0; test < tests; test++ )
{
// if current grade greater than lowGrade, assign it to highGrade
if ( grades[ student ][ test ] > highGrade )
highGrade = grades[ student ][ test ]; // new highest grade
} // end inner for
} // end outer for
return highGrade; // return highest grade
} // end function getMaximum
// determine average grade for particular set of grades
double GradeBook::getAverage( const int setOfGrades[], const int grades )
{
int total = 0; // initialize total
// sum grades in array
for ( int grade = 0; grade < grades; grade++ )
total += setOfGrades[ grade ];
// return average of grades
return static_cast< double >( total ) / grades;
} // end function getAverage
// output bar chart displaying grade distribution
void GradeBook::outputBarChart()
{
cout << "\nOverall grade distribution:" << endl;
// stores frequency of grades in each range of 10 grades
const int frequencySize = 11;
int frequency[ frequencySize ] = { 0 };
// for each grade, increment the appropriate frequency
for ( int student = 0; student < students; student++ )
for ( int test = 0; test < tests; test++ )
++frequency[ grades[ student ][ test ] / 10 ];
// for each grade frequency, print bar in chart
for ( int count = 0; count < frequencySize; count++ )
{
// output bar label ("0-9:", ..., "90-99:", "100:" )
if ( count == 0 )
cout << " 0-9: ";
else if ( count == 10 )
cout << " 100: ";
else
cout << count * 10 << "-" << ( count * 10 ) + 9 << ": ";
// print bar of asterisks
for ( int stars = 0; stars < frequency[ count ]; stars++ )
cout << '*';
cout << endl; // start a new line of output
} // end outer for
} // end function outputBarChart
// output the contents of the grades array
void GradeBook::outputGrades()
{
cout << "\nThe grades are:\n\n";
cout << " "; // align column heads
// create a column heading for each of the tests
for ( int test = 0; test < tests; test++ )
cout << "Test " << test + 1 << " ";
cout << "Average" << endl; // student average column heading
// create rows/columns of text representing array grades
for ( int student = 0; student < students; student++ )
{
cout << "Student " << setw( 2 ) << student + 1;
// output student's grades
for ( int test = 0; test < tests; test++ )
cout << setw( 8 ) << grades[ student ][ test ];
// call member function getAverage to calculate student's average;
// pass row of grades and the value of tests as the arguments
double average = getAverage( grades[ student ], tests );
cout << setw( 9 ) << setprecision( 2 ) << fixed << average << endl;
} // end outer for
} // end function outputGrades
/**************************************************************************
* (C) Copyright 1992-2005 by Deitel & Associates, Inc. and *
* Pearson Education, Inc. All Rights Reserved. *
* *
* DISCLAIMER: The authors and publisher of this book have used their *
* best efforts in preparing the book. These efforts include the *
* development, research, and testing of the theories and programs *
* to determine their effectiveness. The authors and publisher make *
* no warranty of any kind, expressed or implied, with regard to these *
* programs or to the documentation contained in these books. The authors *
* and publisher shall not be liable in any event for incidental or *
* consequential damages in connection with, or arising out of, the *
* furnishing, performance, or use of these programs. *
**************************************************************************/
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