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optimize.cpp
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1 /* -*- mode: C++; c-basic-offset: 2; indent-tabs-mode: nil -*- */
2 /*
3  * Main author:
4  * Christian Schulte <schulte@gecode.org>
5  *
6  * Copyright:
7  * Christian Schulte, 2008
8  *
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33 
34 #include <gecode/minimodel.hh>
35 
36 namespace Gecode {
37 
38  void
40  const IntMinimizeSpace* best =
41  dynamic_cast<const IntMinimizeSpace*>(&_best);
42  if (best == nullptr)
43  throw DynamicCastFailed("IntMinimizeSpace::constrain");
44  rel(*this, cost(), IRT_LE, best->cost().val());
45  }
46 
47 
48  void
50  const IntMaximizeSpace* best =
51  dynamic_cast<const IntMaximizeSpace*>(&_best);
52  if (best == nullptr)
53  throw DynamicCastFailed("IntMaximizeSpace::constrain");
54  rel(*this, cost(), IRT_GR, best->cost().val());
55  }
56 
57 
58  void
60  const IntLexMinimizeSpace* best =
61  dynamic_cast<const IntLexMinimizeSpace*>(&_best);
62  if (best == nullptr)
63  throw DynamicCastFailed("IntLexMinimizeSpace::constrain");
64  IntVarArgs cx(cost()), bx(best->cost());
65  IntArgs bn(bx.size());
66  for (int i=bn.size(); i--; )
67  bn[i] = bx[i].val();
68  rel(*this, cx, IRT_LE, bn);
69  }
70 
71  void
73  const IntLexMaximizeSpace* best =
74  dynamic_cast<const IntLexMaximizeSpace*>(&_best);
75  if (best == nullptr)
76  throw DynamicCastFailed("IntLexMaximizeSpace::constrain");
77  IntVarArgs cx(cost()), bx(best->cost());
78  IntArgs bn(bx.size());
79  for (int i=bn.size(); i--; )
80  bn[i] = bx[i].val();
81  rel(*this, cx, IRT_GR, bn);
82  }
83 
84 #ifdef GECODE_HAS_FLOAT_VARS
85 
86  void
88  const FloatMinimizeSpace* best =
89  dynamic_cast<const FloatMinimizeSpace*>(&_best);
90  if (best == nullptr)
91  throw DynamicCastFailed("FloatMinimizeSpace::constrain");
92  rel(*this, cost(), FRT_LE, best->cost().val()-step);
93  }
94 
95 
96  void
98  const FloatMaximizeSpace* best =
99  dynamic_cast<const FloatMaximizeSpace*>(&_best);
100  if (best == nullptr)
101  throw DynamicCastFailed("FloatMaximizeSpace::constrain");
102  rel(*this, cost(), FRT_GR, best->cost().val()+step);
103  }
104 
105 #endif
106 
107 }
108 
109 // STATISTICS: minimodel-search
110 
@ FRT_LE
Less ( )
Definition: float.hh:1072
FloatNum step
Step by which a next solution has to have lower cost.
Definition: minimodel.hh:2474
virtual IntVar cost(void) const =0
Return variable with current cost.
FloatNum step
Step by which a next solution has to have lower cost.
Definition: minimodel.hh:2449
virtual void constrain(const Space &best)
Member function constraining according to decreasing cost.
Definition: optimize.cpp:39
FloatVal val(void) const
Return assigned value.
Definition: float.hpp:53
Passing integer variables.
Definition: int.hh:656
@ IRT_LE
Less ( )
Definition: int.hh:929
Class for lexicographically minimizing integer costs.
Definition: minimodel.hh:2405
Class for maximizing integer cost.
Definition: minimodel.hh:2388
Computation spaces.
Definition: core.hpp:1742
virtual void constrain(const Space &best)
Member function constraining according to increasing cost.
Definition: optimize.cpp:49
@ FRT_GR
Greater ( )
Definition: float.hh:1074
virtual void constrain(const Space &best)
Member function constraining according to cost.
Definition: optimize.cpp:87
Exception: dynamic cast failed
Definition: exception.hpp:69
virtual IntVarArgs cost(void) const =0
Return variables with current costs.
Gecode toplevel namespace
virtual IntVar cost(void) const =0
Return variable with current cost.
Class for lexicographically maximizing integer costs.
Definition: minimodel.hh:2422
virtual void constrain(const Space &best)
Member function constraining according to increasing costs.
Definition: optimize.cpp:72
Class for minimizing integer cost.
Definition: minimodel.hh:2371
virtual FloatVar cost(void) const =0
Return variable with current cost.
Class for maximizing float cost.
Definition: minimodel.hh:2471
void rel(Home home, FloatVar x0, FloatRelType frt, FloatVal n)
Propagates .
Definition: rel.cpp:43
virtual void constrain(const Space &best)
Member function constraining according to cost.
Definition: optimize.cpp:97
virtual FloatVar cost(void) const =0
Return variable with current cost.
virtual void constrain(const Space &best)
Member function constraining according to decreasing costs.
Definition: optimize.cpp:59
virtual IntVarArgs cost(void) const =0
Return variables with current costs.
int val(void) const
Return assigned value.
Definition: int.hpp:56
Class for minimizing float cost.
Definition: minimodel.hh:2446
@ IRT_GR
Greater ( )
Definition: int.hh:931
Passing integer arguments.
Definition: int.hh:628
Gecode::IntArgs i({1, 2, 3, 4})