kbruch/src/ratio.h

   1 /***************************************************************************
   2                           ratio.h  -  class ratio
   3                              -------------------
   4     begin                : Tue Nov 27 16:40:42 CET 2001
   5     copyright            : (C) 2001-2004 by Sebastian Stein
   6     email                : seb.kde@hpfsc.de
   7  ***************************************************************************/
   8
   9 /***************************************************************************
  10  *                                                                         *
  11  *   This program is free software; you can redistribute it and/or modify  *
  12  *   it under the terms of the GNU General Public License as published by  *
  13  *   the Free Software Foundation; either version 2 of the License, or     *
  14  *   (at your option) any later version.                                   *
  15  *                                                                         *
  16  ***************************************************************************/
  17
  18 #ifndef RATIO_H
  19 #define RATIO_H
  20
  21 #include <qtextstream.h>
  22
  23 /** Represents a ratio
  24  *  This class represents 1 ratio. There are several functions provided to
  25  *  modify the numerator and denominator. It is also possible to calculate with
  26  *  objects of the class ratio. Overloaded operation functions are provided for
  27  *  this task.
  28  *  \author Sebastian Stein */
  29 class ratio
  30 {
  31 public:
  32         /** constructor */
  33         ratio(int pnumerator = 0, int pdenominator = 1);
  34
  35         /** copy constructor */
  36         ratio(const ratio & copy_ratio);
  37
  38         /** destructor */
  39         ~ratio();
  40
  41         /** returns the ratio as QTextStream object */
  42         QTextStream & display(QTextStream & str) const;
  43
  44         /** returns the numerator */
  45         int numerator() const;
  46
  47         /** returns the denominator */
  48         int denominator() const;
  49
  50         /** set numerator and reduce the ratio */
  51         void setNumerator(int pnumerator = 0, bool reduce = true);
  52
  53         /** set denominator and reduce the ratio */
  54         void setDenominator(int pdenominator = 1, bool reduce = true);
  55
  56         /** operator overloading for: c = object + summand */
  57         ratio operator+(ratio addend);
  58
  59         /** operator overloading for: c = object - subtrahend */
  60         ratio operator-(ratio subtrahend);
  61
  62         /** operator overloading for: c = object * factor */
  63         ratio operator*(ratio factor);
  64
  65         /** operator overloading for: c = object / divisor */
  66         ratio operator/(ratio divisor);
  67
  68         /** set numerator with dummy and denominator = 1 */
  69         ratio operator=(int dummy);
  70
  71         /** compares the current ratio with a given one */
  72         bool operator==(ratio right);
  73
  74         /** compares the current ratio with a given one */
  75         bool operator<(ratio right);
  76
  77         /** compares the current ratio with a given one */
  78         bool operator>(ratio right);
  79
  80         /** exchange numerator and denominator */
  81         void reziproc();
  82
  83         /** reduce the ratio */
  84         void reduce();
  85 private:
  86         /** numerator */
  87         int m_numerator;
  88
  89         /** denominator */
  90         int m_denominator;
  91
  92         /** change sign of the ratio */
  93         void change_sign();
  94 }
  95 ;
  96
  97 /* ------ some prototyps of non class functions ------ */
  98
  99 /** it is possible to code: cout << ratio_object << endl; */
 100 QTextStream & operator<<(QTextStream & str, const ratio & pratio);
 101
 102 #endif