1 /**
2  * Implements a complex number type.
3  *
4  * Copyright:   Copyright (C) 1999-2020 by The D Language Foundation, All Rights Reserved
5  * Authors:     $(LINK2 http://www.digitalmars.com, Walter Bright)
6  * License:     $(LINK2 http://www.boost.org/LICENSE_1_0.txt, Boost License 1.0)
7  * Source:      $(LINK2 https://github.com/dlang/dmd/blob/master/src/dmd/complex.d, _complex.d)
8  * Documentation:  https://dlang.org/phobos/dmd_complex.html
9  * Coverage:    https://codecov.io/gh/dlang/dmd/src/master/src/dmd/complex.d
10  */
11 
12 module dmd.complex;
13 
14 import dmd.root.ctfloat;
15 
16 extern (C++) struct complex_t
17 {
18     real_t re;
19     real_t im;
20 
21     this() @disable;
22 
23     this(real_t re)
24     {
25         this(re, CTFloat.zero);
26     }
27 
28     this(real_t re, real_t im)
29     {
30         this.re = re;
31         this.im = im;
32     }
33 
34     extern (D) complex_t opBinary(string op)(complex_t y)
35         if (op == "+")
36     {
37         return complex_t(re + y.re, im + y.im);
38     }
39 
40     extern (D) complex_t opBinary(string op)(complex_t y)
41         if (op == "-")
42     {
43         return complex_t(re - y.re, im - y.im);
44     }
45 
46     extern (D) complex_t opUnary(string op)()
47         if (op == "-")
48     {
49         return complex_t(-re, -im);
50     }
51 
52     extern (D) complex_t opBinary(string op)(complex_t y)
53         if (op == "*")
54     {
55         return complex_t(re * y.re - im * y.im, im * y.re + re * y.im);
56     }
57 
58     extern (D) complex_t opBinaryRight(string op)(real_t x)
59         if (op == "*")
60     {
61         return complex_t(x) * this;
62     }
63 
64     extern (D) complex_t opBinary(string op)(real_t y)
65         if (op == "*")
66     {
67         return this * complex_t(y);
68     }
69 
70     extern (D) complex_t opBinary(string op)(real_t y)
71         if (op == "/")
72     {
73         return this / complex_t(y);
74     }
75 
76     extern (D) complex_t opBinary(string op)(complex_t y)
77         if (op == "/")
78     {
79         if (CTFloat.fabs(y.re) < CTFloat.fabs(y.im))
80         {
81             const r = y.re / y.im;
82             const den = y.im + r * y.re;
83             return complex_t((re * r + im) / den, (im * r - re) / den);
84         }
85         else
86         {
87             const r = y.im / y.re;
88             const den = y.re + r * y.im;
89             return complex_t((re + r * im) / den, (im - r * re) / den);
90         }
91     }
92 
93     extern (D) bool opCast(T : bool)() const
94     {
95         return re || im;
96     }
97 
98     int opEquals(complex_t y) const
99     {
100         return re == y.re && im == y.im;
101     }
102 }
103 
104 extern (C++) real_t creall(complex_t x)
105 {
106     return x.re;
107 }
108 
109 extern (C++) real_t cimagl(complex_t x)
110 {
111     return x.im;
112 }