fraction.cpp

A Fraction class that has the ability to add, subtract, multiply, divide and show various statistics

//--------------------------------------------------------------
//
// F R A C T I O N  C L A S S
//
// F R A C T I O N . C P P
//
// Version 1.1, Copyright (C) 2001, by Daniel Pronych
//
// FREEDOM to USE and DISTRIBUTE is LIMITED ONLY TO THE
// EDITTING OF THIS TITLE ON THIS, and ALL ACCOMPANYING FILES.
// THIS FILE IS PLACED INTO PUBLIC DOMAIN in hopes that it
// might be found useful for others.  It is not FORCEFULLY 
// placed into public domain but with consent from the AUTHOR.
//
// C L A S S  D E S C R I P T I O N
// --------------------------------
//
// This file, provides a body to the functions declared in 
// Fraction.h and must not be seperated from it, lest it stop 
// functioning and benefit no one.
//
// This Fraction class allows extreme flexibility in working
// with fractions.  When a fraction is declared and the user
// and or client program implements a fraction with a negative
// denominator this class quickly distributes it to both the
// numinator and denominator to keep with what one would 
// normally do with Fractions in a Math class.  Operators are
// defined to work with extreme ease for the user of this class.
// A Reduce fraction is included to allow the user to use to
// simply the fraction that they are dealing with.
//
// Pre/Post conditions have been added to simplify the Class.
//
// Have fun with this class!
//--------------------------------------------------------------
Fraction::Fraction()
	:num(0), den(1) // Sets default values for Fraction Class
{
	// Constructor has no need to initialize any other code
	// in it's current state
}
//-----------------------------------------------------
Fraction::~Fraction()
{
	// Deconstructor contains no code at the moment
}
//-----------------------------------------------------
void Fraction::SetNum(BIGGEST_INT newnum)
//pre : Call to set the numerator
//post: new numerator is set
{
	num = newnum;
}

//-----------------------------------------------------
void Fraction::SetDen(BIGGEST_INT newden)
// pre : Call to set the deminator
// post: Validate if negative and set new denominator
{
	den = newden;
	if(den < 0) {
		num *= -1;
		den *= -1;
	}
}
//-----------------------------------------------------
void Fraction::SetAll(int Fracnum)
// pre : Fraction is defined, and program seeks input from user
// post: User has given two values and if denominator is 
//		 negative it is now made positive
{
	BIGGEST_INT newnum = 0, newden = 0;
	cout << "\nEnter a value for the numerator in Fraction " << Fracnum << ". ";
	cin >> num;
	cout << "\nEnter a value for the denominator in Fraction " << Fracnum << ". ";
	cin >> den;

	if(den < 0) { // Choke out negative denominators as soon as they are inputted.
		num *= -1;
		den *= -1;
	}
}
//-----------------------------------------------------
BIGGEST_INT Fraction::Num()
// pre: any call made to use numerator in Fraction class
{
	return(num);
}
//-----------------------------------------------------
BIGGEST_INT Fraction::Den()
// pre: any call made to use denominator in Fraction class
{
	return(den);
}
//-----------------------------------------------------
void Fraction::Reduce()
// pre : Function is called with a Fraction to reduce
// post: Function is reduced as far as possible
{
	BIGGEST_INT rdc = 0; // Reduce value
	if(den > num) // Makes sure the greater number is sent to the Function first
		rdc = GCD(den, num);
	else if(den < num)
		rdc = GCD(num, den);
	else
		rdc = GCD(num, den);
	num /= rdc; // Simplifies Fraction's Numerator
	den /= rdc; // Simplifies Fraction's Denominator
}
//-----------------------------------------------------
void Fraction::DisplayMixed()
{
	cout << "Mixed value: " << num / den << " " << num % den << "/";
	if(den < 0) /* Don't let the denominator of the mixed number appear negative
					if the value is negative it's displayed in the whole number. */
		cout << den * -1;
	else
		cout << den;
	cout << endl;
}
//-----------------------------------------------------
float FracDecVal(Fraction a)
// pre: Function is given one fraction to find the decimal value of
// post: Function returns the decimal value of given fraction
{
	float fracnum = a.num; // Make numerator a floater to prevent loss of data
	float fracden = a.den; // Make denominator a floater to prevent loss of data
	float decval = fracnum / fracden; // Decimal value variable
	return(decval);
}
//-----------------------------------------------------
BIGGEST_INT Fraction::GCD(int num1, int remainder)
// pre : Function is given two values (numerator and denominator)
// post: Function returns the greatest common factor to client
{
	if(remainder == 0)
		return(num1);
	else {
		return(GCD(remainder,num1%remainder));
	}
}
//-----------------------------------------------------
Fraction Fraction::operator +(Fraction d)
// pre : Function is given two valid Fractions to add
// post: Function returns the added value of the Fractions as is
{
	Fraction retfrac;
	retfrac.num = (num * d.den) + (d.num * den);
	retfrac.den = d.den * den;
	return(retfrac);
}
//-----------------------------------------------------
Fraction Fraction::operator -(Fraction d)
// pre : Function is given two valid Fractions to subtract
// post: Function returns the subtracted value of the Fraction as is
{
	Fraction retfrac;
	retfrac.num = (num * d.den) - (d.num * d.den);
	retfrac.den = d.den * den;
	return(retfrac);
}
//-----------------------------------------------------
Fraction Fraction::operator *(Fraction d)
// pre : Function is given two valid Fractions to multiply
// post: Function returns the multiplied value of the Fraction as is
{
	Fraction retfrac;
	retfrac.num = num * d.num;
	retfrac.den = den * d.den;
	return(retfrac);
}
//-----------------------------------------------------
Fraction Fraction::operator /(Fraction d)
// pre : Function is given two valid Fractions to divide
// post: Function returns the divided value of the Fraction as is
{
	Fraction retfrac;
	retfrac.num = num * d.den;
	retfrac.den = den * d.num;
	if(retfrac.den < 0) { // Just in case the inversion caused the denominator to be negative
		retfrac.num *= -1;
		retfrac.den *= -1;
	}
	return(retfrac);
}
//-----------------------------------------------------
Fraction Fraction_Do_Op(int operation, Fraction a, Fraction b) 
// pre : Function is given operation and two Fractions
// post: Function completes the operation and returns to client
{
	Fraction rc;
	switch (operation) {
	case FRAC_ADD:
		return (a + b);
	case FRAC_SUB:
		return (a - b);
	case FRAC_MUL:
		return (a * b);
	case FRAC_DIV:
		return (a / b);
	}
	rc.SetNum(1);
	rc.SetDen(1);
	return (rc);
}
//-----------------------------------------------------