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00001 00002 // 00003 // Copyright (c) 2006, Industrial Light & Magic, a division of Lucas 00004 // Digital Ltd. LLC 00005 // 00006 // All rights reserved. 00007 // 00008 // Redistribution and use in source and binary forms, with or without 00009 // modification, are permitted provided that the following conditions are 00010 // met: 00011 // * Redistributions of source code must retain the above copyright 00012 // notice, this list of conditions and the following disclaimer. 00013 // * Redistributions in binary form must reproduce the above 00014 // copyright notice, this list of conditions and the following disclaimer 00015 // in the documentation and/or other materials provided with the 00016 // distribution. 00017 // * Neither the name of Industrial Light & Magic nor the names of 00018 // its contributors may be used to endorse or promote products derived 00019 // from this software without specific prior written permission. 00020 // 00021 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 00022 // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 00023 // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 00024 // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 00025 // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 00026 // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 00027 // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 00028 // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 00029 // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 00030 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 00031 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 00032 // 00034 00035 00036 #ifndef INCLUDED_IMF_RATIONAL_H 00037 #define INCLUDED_IMF_RATIONAL_H 00038 00039 //----------------------------------------------------------------------------- 00040 // 00041 // Rational numbers 00042 // 00043 // A rational number is represented as pair of integers, n and d. 00044 // The value of of the rational number is 00045 // 00046 // n/d for d > 0 00047 // positive infinity for n > 0, d == 0 00048 // negative infinity for n < 0, d == 0 00049 // not a number (NaN) for n == 0, d == 0 00050 // 00051 //----------------------------------------------------------------------------- 00052 00053 namespace Imf { 00054 00055 class Rational 00056 { 00057 public: 00058 00059 int n; // numerator 00060 unsigned int d; // denominator 00061 00062 00063 //---------------------------------------- 00064 // Default constructor, sets value to zero 00065 //---------------------------------------- 00066 00067 Rational (): n (0), d (1) {} 00068 00069 00070 //------------------------------------- 00071 // Constructor, explicitly sets n and d 00072 //------------------------------------- 00073 00074 Rational (int n, int d): n (n), d (d) {} 00075 00076 00077 //---------------------------- 00078 // Constructor, approximates x 00079 //---------------------------- 00080 00081 explicit Rational (double x); 00082 00083 00084 //--------------------------------- 00085 // Approximate conversion to double 00086 //--------------------------------- 00087 00088 operator double () const {return double (n) / double (d);} 00089 }; 00090 00091 } // namespace Imf 00092 00093 #endif