1    package math; 
2     
3    public class Complex { 
4      private double real; 
5      private double imaginary; 
6     
7      public Complex(double _x, double _y) { 
8        real = _x; 
9        imaginary = _y; 
10     } 
11    
12     public Complex() { 
13       real = 0; 
14       imaginary = 0; 
15     } 
16    
17     public void set(double _x, double _y) { 
18       real = _x; 
19       imaginary = _y; 
20     } 
21    
22     public void setReal(double _x) { 
23       real = _x; 
24     } 
25    
26     public void setImaginary(double _i) { 
27       imaginary = _i; 
28     } 
29    
30     public void addReal(double _x) { 
31       real += _x; 
32     } 
33    
34     public void addImaginary(double _i) { 
35       imaginary += _i; 
36     } 
37    
38     public double getReal() { 
39       return real; 
40     } 
41    
42     public double getImaginary() { 
43       return imaginary; 
44     } 
45    
46     // c = a + b, c=a.plus(b) 
47     public Complex plus(Complex b) { 
48       return new Complex( 
49           b.real + real, 
50           b.imaginary + imaginary); 
51     } 
52    
53     // c = a - b, c=a.minus(b); 
54     public Complex minus(Complex b) { 
55       return new Complex( 
56           real - b.real, 
57           imaginary - b.imaginary); 
58     } 
59    
60     // c = a * b, c=a.times(b); 
61     //(x1 + iy1)(x2 + iy2) = 
62     //      x1        *  x2    - y1        * y2 + 
63     //    i(y1        *  x2    + x1        * y2) 
64     public Complex times(Complex b) { 
65       return new Complex( 
66           real * b.real - imaginary * b.imaginary, 
67           imaginary * b.real + real * b.imaginary); 
68     } 
69    
70     // c = a.abs() 
71     public Complex abs() { 
72       return new Complex( 
73           Math.abs(real), 
74           Math.abs(imaginary) 
75       ); 
76     } 
77    
78     // c = 1/a, c=inverse(a); 
79     public Complex inverse() { 
80       double m = square(); 
81       return new Complex( 
82           real / m, 
83           -imaginary / m 
84       ); 
85     } 
86    
87     // c = a^2, c = a.square(); 
88     public double square() { 
89       return real * real + imaginary * imaginary; 
90     } 
91    
92     // c = |a|, c=a.magnitude() 
93     public double magnitude() { 
94       return Math.sqrt(square()); 
95     } 
96    
97     // makes a copy of this 
98     // c = a.copy(); 
99     public Complex copy() { 
100      return new Complex(real, imaginary); 
101    } 
102   
103    public void print() { 
104      System.out.println("Complex: real = " + real + " Imaginary = " + imaginary); 
105    } 
106   
107    public void print(String msg) { 
108      System.out.println(msg + "(" + real + "," + imaginary + ")"); 
109    } 
110  }