complex.C

#include <iostream.h>
#include <math.h>
#include <stdlib.h>

class Complex {
    public:
        Complex(); //Default constructor
        ~Complex(); //Default destructor.
        void Set(double new_real, double new_imaginary); //Set data members.
        double Real(); //Return the real part.
        double Imaginary(); //Return the imaginary part.
        Complex operator+(Complex); //Overloaded + operator
        Complex operator*(Complex); //Overloaded * operator
        Complex operator=(Complex); //Overloaded = operator
        int operator==(Complex); //Overloaded == operator
    private:
        double real;
        double imaginary;
};

//Complex constructor, initialises to 0 + i0.
Complex::Complex() {
    real = 0;
    imaginary = 0;
}

//Complex destructor.
Complex::~Complex() {};

//Overloaded = operator.
Complex Complex::operator=(Complex c) {
    if (&c != this) {
        real = c.Real();
        imaginary = c.Imaginary();
        return *this;
    }
}

//Overloaded + operator.
Complex Complex::operator+(Complex c) {
    Complex tmp;
    double new_real, new_imaginary;
    new_real = real + c.Real();
    new_imaginary = imaginary + c.Imaginary();
    tmp.Set(new_real,new_imaginary);
    return tmp;
}

//Overloaded * operator.
Complex Complex::operator*(Complex c) {
    Complex tmp;
    double new_real, new_imaginary;
    new_real = real * c.Real() - imaginary * c.Imaginary();
    new_imaginary = real * c.Imaginary() + imaginary * c.Real();
    tmp.Set(new_real,new_imaginary);
    return tmp;
}

//Overloaded == operator. Small error tolerances.
int Complex::operator==(Complex c) {
    //This is to take care of round off errors.
    if (fabs(c.Real() - real) > pow(10,-14)) {
        return 0;
    }
    if (fabs(c.Imaginary()- imaginary) > pow(10,-14)) {
        return 0;
    }
    return 1;
}

//Sets private data members.
void Complex::Set(double new_real, double new_imaginary) {
    real = new_real;
    imaginary = new_imaginary;
}

//Returns the real part of the complex number.
double Complex::Real() {
    return real;
}

//Returns the imaginary part of the complex number.
double Complex::Imaginary() {
    return imaginary;
}