headers/libs/linprog/Variable.h

   1 /*
   2  * Copyright 2007-2008, Christof Lutteroth, lutteroth@cs.auckland.ac.nz
   3  * Copyright 2007-2008, James Kim, jkim202@ec.auckland.ac.nz
   4  * Distributed under the terms of the MIT License.
   5  */
   6 #ifndef VARIABLE_H
   7 #define VARIABLE_H
   8
   9
  10 #include <ObjectList.h>
  11 #include <String.h>
  12
  13 namespace LinearProgramming {
  14
  15 class Constraint;
  16 class LinearSpec;
  17 class Summand;
  18
  19 /**
  20  * Contains minimum and maximum values.
  21  */
  22 class Variable {
  23 public:
  24                         int32                           Index() const;
  25                         int32                           GlobalIndex() const;
  26                         LinearSpec*                     LS() const;
  27                         double                          Value() const;
  28                         void                            SetValue(double value);
  29                         double                          Min() const;
  30                         void                            SetMin(double min);
  31                         double                          Max() const;
  32                         void                            SetMax(double max);
  33                         void                            SetRange(double min, double max);
  34
  35                         const char*                     Label();
  36                         void                            SetLabel(const char* label);
  37
  38                         BString                         ToString() const;
  39
  40                         Constraint*                     IsEqual(Variable* var);
  41                         Constraint*                     IsSmallerOrEqual(Variable* var);
  42                         Constraint*                     IsGreaterOrEqual(Variable* var);
  43
  44                         Constraint*                     IsEqual(Variable* var,
  45                                                                         double penaltyNeg, double penaltyPos);
  46                         Constraint*                     IsSmallerOrEqual(Variable* var,
  47                                                                         double penaltyNeg, double penaltyPos);
  48                         Constraint*                     IsGreaterOrEqual(Variable* var,
  49                                                                         double penaltyNeg, double penaltyPos);
  50
  51                         bool                            IsValid();
  52                         //! Dangerous the variable don't belong to the LinearSpec anymore,
  53                         //! delete it yourself!
  54                         void                            Invalidate();
  55
  56         virtual                                         ~Variable();
  57
  58 protected:
  59                                                                 Variable(LinearSpec* ls);
  60
  61                         //! returns the ref count
  62                         int32                           AddReference();
  63                         int32                           RemoveReference();
  64 private:
  65                         LinearSpec*                     fLS;
  66
  67                         double                          fValue;
  68                         double                          fMin;
  69                         double                          fMax;
  70                         BString                         fLabel;
  71
  72                         bool                            fIsValid;
  73
  74                         int32                           fReferenceCount;
  75 public:
  76         friend class            LinearSpec;
  77 };
  78
  79
  80 typedef BObjectList<Variable> VariableList;
  81
  82
  83 }       // namespace LinearProgramming
  84
  85 using LinearProgramming::Variable;
  86 using LinearProgramming::VariableList;
  87
  88 #endif  // VARIABLE_H