CoinUtils  2.10.14
CoinPresolveFixed.hpp
Go to the documentation of this file.
1 /* $Id: CoinPresolveFixed.hpp 1510 2011-12-08 23:56:01Z lou $ */
2 // Copyright (C) 2002, International Business Machines
3 // Corporation and others. All Rights Reserved.
4 // This code is licensed under the terms of the Eclipse Public License (EPL).
5 
6 #ifndef CoinPresolveFixed_H
7 #define CoinPresolveFixed_H
8 #define FIXED_VARIABLE 1
9 
26  public:
30  struct action {
31  int col;
32  int start;
33  double sol;
34  };
36  int *colrows_;
38  double *colels_;
40  int nactions_;
43 
44  private:
46  remove_fixed_action(int nactions,
47  action *actions,
48  double * colels,
49  int * colrows,
50  const CoinPresolveAction *next);
51 
52  public:
54  const char *name() const;
55 
64  int *fcols,
65  int nfcols,
66  const CoinPresolveAction *next);
67 
68  void postsolve(CoinPostsolveMatrix *prob) const;
69 
72 };
73 
74 
83  const CoinPresolveAction *next);
84 
85 
96 
98  struct action {
99  double bound;
100  int col ;
101  };
102 
106  const action *actions_;
107 
112  const bool fix_to_lower_;
113 
118 
120  make_fixed_action(int nactions, const action *actions, bool fix_to_lower,
121  const remove_fixed_action *faction,
122  const CoinPresolveAction *next)
124  nactions_(nactions), actions_(actions),
125  fix_to_lower_(fix_to_lower),
126  faction_(faction)
127  {}
128 
129  public:
131  const char *name() const;
132 
141  int *fcols,
142  int nfcols,
143  bool fix_to_lower,
144  const CoinPresolveAction *next);
145 
150  void postsolve(CoinPostsolveMatrix *prob) const;
151 
153  virtual ~make_fixed_action() {
155  delete faction_;
156  }
157 };
158 
167  const CoinPresolveAction *next) ;
168 
181 #endif
remove_fixed_action::nactions_
int nactions_
Number of entries in actions_.
Definition: CoinPresolveFixed.hpp:40
remove_fixed_action::action
Structure to hold information necessary to reintroduce a column into the problem representation.
Definition: CoinPresolveFixed.hpp:30
make_fixed_action::transferCosts
void transferCosts(CoinPresolveMatrix *prob)
Transfer costs from singleton variables.
make_fixed_action::faction_
const remove_fixed_action * faction_
The postsolve object with the information required to repopulate the fixed columns.
Definition: CoinPresolveFixed.hpp:117
remove_fixed_action::action::col
int col
column index of variable
Definition: CoinPresolveFixed.hpp:31
remove_fixed_action::remove_fixed
const CoinPresolveAction * remove_fixed(CoinPresolveMatrix *prob, const CoinPresolveAction *next)
Scan the problem for fixed columns and remove them.
remove_fixed_action::action::sol
double sol
value of variable
Definition: CoinPresolveFixed.hpp:33
remove_fixed_action::colrows_
int * colrows_
Array of row indices for coefficients of excised columns.
Definition: CoinPresolveFixed.hpp:36
remove_fixed_action::remove_fixed_action
remove_fixed_action(int nactions, action *actions, double *colels, int *colrows, const CoinPresolveAction *next)
Constructor.
remove_fixed_action
Excise fixed variables from the model.
Definition: CoinPresolveFixed.hpp:25
make_fixed_action
Fix a variable at a specified bound.
Definition: CoinPresolveFixed.hpp:95
make_fixed_action::postsolve
void postsolve(CoinPostsolveMatrix *prob) const
Postsolve (unfix variables)
make_fixed_action::name
const char * name() const
Returns string "make_fixed_action".
CoinPresolveAction::next
const CoinPresolveAction * next
The next presolve transformation.
Definition: CoinPresolveMatrix.hpp:171
make_fixed_action::~make_fixed_action
virtual ~make_fixed_action()
Destructor.
Definition: CoinPresolveFixed.hpp:153
make_fixed_action::presolve
static const CoinPresolveAction * presolve(CoinPresolveMatrix *prob, int *fcols, int nfcols, bool fix_to_lower, const CoinPresolveAction *next)
Perform actions to fix variables and return postsolve object.
CoinPostsolveMatrix
Augments CoinPrePostsolveMatrix with information about the problem that is only needed during postsol...
Definition: CoinPresolveMatrix.hpp:1422
remove_fixed_action::presolve
static const remove_fixed_action * presolve(CoinPresolveMatrix *prob, int *fcols, int nfcols, const CoinPresolveAction *next)
Excise the specified columns.
make_fixed_action::nactions_
int nactions_
Number of preserved bounds.
Definition: CoinPresolveFixed.hpp:104
remove_fixed_action::~remove_fixed_action
virtual ~remove_fixed_action()
Destructor.
remove_fixed_action::postsolve
void postsolve(CoinPostsolveMatrix *prob) const
Apply the postsolve transformation for this particular presolve action.
remove_fixed_action::action::start
int start
start of coefficients in colels_ and colrows_
Definition: CoinPresolveFixed.hpp:32
make_fixed_action::fix_to_lower_
const bool fix_to_lower_
True to fix at lower bound, false to fix at upper bound.
Definition: CoinPresolveFixed.hpp:112
CoinPresolveAction
Abstract base class of all presolve routines.
Definition: CoinPresolveMatrix.hpp:156
make_fixed_action::make_fixed
const CoinPresolveAction * make_fixed(CoinPresolveMatrix *prob, const CoinPresolveAction *next)
Scan variables and fix any with equal bounds.
make_fixed_action::action::col
int col
column index of variable
Definition: CoinPresolveFixed.hpp:100
deleteAction
#define deleteAction(array, type)
Definition: CoinPresolveMatrix.hpp:38
make_fixed_action::make_fixed_action
make_fixed_action(int nactions, const action *actions, bool fix_to_lower, const remove_fixed_action *faction, const CoinPresolveAction *next)
Constructor.
Definition: CoinPresolveFixed.hpp:120
make_fixed_action::actions_
const action * actions_
Vector of preserved bounds, one for each variable fixed in this object.
Definition: CoinPresolveFixed.hpp:106
make_fixed_action::action
Structure to preserve the bound overwritten when fixing a variable.
Definition: CoinPresolveFixed.hpp:98
remove_fixed_action::name
const char * name() const
Returns string "remove_fixed_action".
make_fixed_action::action::bound
double bound
Value of bound overwritten to fix variable.
Definition: CoinPresolveFixed.hpp:99
remove_fixed_action::colels_
double * colels_
Array of coefficients of excised columns.
Definition: CoinPresolveFixed.hpp:38
CoinPresolveMatrix
Augments CoinPrePostsolveMatrix with information about the problem that is only needed during presolv...
Definition: CoinPresolveMatrix.hpp:836
remove_fixed_action::actions_
action * actions_
Vector specifying variable(s) affected by this object.
Definition: CoinPresolveFixed.hpp:42