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34 
35 
36 #ifndef INCLUDED_IMF_RATIONAL_H
37 #define INCLUDED_IMF_RATIONAL_H
38 
39 //-----------------------------------------------------------------------------
40 //
41 //	Rational numbers
42 //
43 //	A rational number is represented as pair of integers, n and d.
44 //	The value of of the rational number is
45 //
46 //		n/d			for d > 0
47 //		positive infinity	for n > 0, d == 0
48 //		negative infinity	for n < 0, d == 0
49 //		not a number (NaN)	for n == 0, d == 0
50 //
51 //-----------------------------------------------------------------------------
52 
53 namespace Imf {
54 
55 class Rational
56 {
57   public:
58 
59     int			n;		// numerator
60     unsigned int	d;		// denominator
61 
62 
63     //----------------------------------------
64     // Default constructor, sets value to zero
65     //----------------------------------------
66 
Rational()67     Rational (): n (0), d (1) {}
68 
69 
70     //-------------------------------------
71     // Constructor, explicitly sets n and d
72     //-------------------------------------
73 
Rational(int _n,int _d)74     Rational (int _n, int _d): n (_n), d (_d) {}
75 
76 
77     //----------------------------
78     // Constructor, approximates x
79     //----------------------------
80 
81     explicit Rational (double x);
82 
83 
84     //---------------------------------
85     // Approximate conversion to double
86     //---------------------------------
87 
88     operator double () const {return double (n) / double (d);}
89 };
90 
91 } // namespace Imf
92 
93 #endif
94