Cbc  2.9.9
 All Classes Namespaces Files Functions Variables Typedefs Enumerations Enumerator Friends Macros Groups Pages
Public Member Functions | Protected Attributes | List of all members
CbcClique Class Reference

Branching object for cliques. More...

#include <CbcClique.hpp>

+ Inheritance diagram for CbcClique:
+ Collaboration diagram for CbcClique:

Public Member Functions

 CbcClique ()
 Default Constructor. More...
 
 CbcClique (CbcModel *model, int cliqueType, int numberMembers, const int *which, const char *type, int identifier, int slack=-1)
 Useful constructor (which are integer indices) slack can denote a slack in set. More...
 
 CbcClique (const CbcClique &)
 Copy constructor. More...
 
virtual CbcObjectclone () const
 Clone. More...
 
CbcCliqueoperator= (const CbcClique &rhs)
 Assignment operator. More...
 
virtual ~CbcClique ()
 Destructor. More...
 
virtual double infeasibility (const OsiBranchingInformation *info, int &preferredWay) const
 Infeasibility - large is 0.5. More...
 
virtual void feasibleRegion ()
 This looks at solution and sets bounds to contain solution. More...
 
virtual CbcBranchingObjectcreateCbcBranch (OsiSolverInterface *solver, const OsiBranchingInformation *info, int way)
 Creates a branching object. More...
 
int numberMembers () const
 Number of members. More...
 
int numberNonSOSMembers () const
 Number of variables with -1 coefficient. More...
 
const int * members () const
 Members (indices in range 0 ... numberIntegers_-1) More...
 
char type (int index) const
 Type of each member, i.e., which way is strong. More...
 
int cliqueType () const
 Clique type: 0 is <=, 1 is ==. More...
 
virtual void redoSequenceEtc (CbcModel *model, int numberColumns, const int *originalColumns)
 Redoes data when sequence numbers change. More...
 
- Public Member Functions inherited from CbcObject
 CbcObject ()
 
 CbcObject (CbcModel *model)
 
 CbcObject (const CbcObject &)
 
CbcObjectoperator= (const CbcObject &rhs)
 
virtual ~CbcObject ()
 Destructor. More...
 
virtual double infeasibility (int &) const
 
virtual double feasibleRegion (OsiSolverInterface *solver, const OsiBranchingInformation *info) const
 Dummy one for compatibility. More...
 
virtual double feasibleRegion (OsiSolverInterface *solver) const
 For the variable(s) referenced by the object, look at the current solution and set bounds to match the solution. More...
 
virtual OsiBranchingObjectcreateBranch (OsiSolverInterface *, const OsiBranchingInformation *, int) const
 Create a branching object and indicate which way to branch first. More...
 
virtual OsiBranchingObjectcreateOsiBranch (OsiSolverInterface *solver, const OsiBranchingInformation *info, int way) const
 Create an Osibranching object and indicate which way to branch first. More...
 
virtual OsiSolverBranchsolverBranch () const
 Create an OsiSolverBranch object. More...
 
virtual CbcBranchingObjectpreferredNewFeasible () const
 Given a valid solution (with reduced costs, etc.), return a branching object which would give a new feasible point in a good direction. More...
 
virtual CbcBranchingObjectnotPreferredNewFeasible () const
 Given a valid solution (with reduced costs, etc.), return a branching object which would give a new feasible point in a bad direction. More...
 
virtual void resetBounds (const OsiSolverInterface *)
 Reset variable bounds to their original values. More...
 
virtual void floorCeiling (double &floorValue, double &ceilingValue, double value, double tolerance) const
 Returns floor and ceiling i.e. More...
 
virtual CbcObjectUpdateData createUpdateInformation (const OsiSolverInterface *solver, const CbcNode *node, const CbcBranchingObject *branchingObject)
 Pass in information on branch just done and create CbcObjectUpdateData instance. More...
 
virtual void updateInformation (const CbcObjectUpdateData &)
 Update object by CbcObjectUpdateData. More...
 
int id () const
 Identifier (normally column number in matrix) More...
 
void setId (int value)
 Set identifier (normally column number in matrix) but 1000000000 to 1100000000 means optional branching object i.e. More...
 
bool optionalObject () const
 Return true if optional branching object i.e. More...
 
int position () const
 Get position in object_ list. More...
 
void setPosition (int position)
 Set position in object_ list. More...
 
void setModel (CbcModel *model)
 update model More...
 
CbcModelmodel () const
 Return model. More...
 
int preferredWay () const
 If -1 down always chosen first, +1 up always, 0 normal. More...
 
void setPreferredWay (int value)
 Set -1 down always chosen first, +1 up always, 0 normal. More...
 
virtual void initializeForBranching (CbcModel *)
 Initialize for branching. More...
 
- Public Member Functions inherited from OsiObject
 OsiObject ()
 Default Constructor. More...
 
 OsiObject (const OsiObject &)
 Copy constructor. More...
 
OsiObjectoperator= (const OsiObject &rhs)
 Assignment operator. More...
 
virtual ~OsiObject ()
 Destructor. More...
 
double infeasibility (const OsiSolverInterface *solver, int &whichWay) const
 Infeasibility of the object. More...
 
virtual double checkInfeasibility (const OsiBranchingInformation *info) const
 
virtual bool canDoHeuristics () const
 Return true if object can take part in normal heuristics. More...
 
virtual bool canMoveToNearest () const
 Return true if object can take part in move to nearest heuristic. More...
 
virtual int columnNumber () const
 Column number if single column object -1 otherwise, Used by heuristics. More...
 
int priority () const
 Return Priority - note 1 is highest priority. More...
 
void setPriority (int priority)
 Set priority. More...
 
virtual bool boundBranch () const
 Return true if branch should only bound variables. More...
 
virtual bool canHandleShadowPrices () const
 Return true if knows how to deal with Pseudo Shadow Prices. More...
 
int numberWays () const
 Return maximum number of ways branch may have. More...
 
void setNumberWays (int numberWays)
 Set maximum number of ways branch may have. More...
 
void setWhichWay (int way)
 Return preferred way to branch. More...
 
int whichWay () const
 Return current preferred way to branch. More...
 
double infeasibility () const
 Return infeasibility. More...
 
virtual double upEstimate () const
 Return "up" estimate (default 1.0e-5) More...
 
virtual double downEstimate () const
 Return "down" estimate (default 1.0e-5) More...
 
virtual void resetSequenceEtc (int, const int *)
 Change column numbers after preprocessing. More...
 
virtual void updateBefore (const OsiObject *)
 Updates stuff like pseudocosts before threads. More...
 
virtual void updateAfter (const OsiObject *, const OsiObject *)
 Updates stuff like pseudocosts after threads finished. More...
 

Protected Attributes

int numberMembers_
 data Number of members More...
 
int numberNonSOSMembers_
 Number of Non SOS members i.e. fixing to zero is strong. More...
 
int * members_
 Members (indices in range 0 ... numberIntegers_-1) More...
 
char * type_
 Strong value for each member. More...
 
int cliqueType_
 Clique type. More...
 
int slack_
 Slack variable for the clique. More...
 
- Protected Attributes inherited from CbcObject
CbcModelmodel_
 data More...
 
int id_
 Identifier (normally column number in matrix) More...
 
int position_
 Position in object list. More...
 
int preferredWay_
 If -1 down always chosen first, +1 up always, 0 normal. More...
 
- Protected Attributes inherited from OsiObject
double infeasibility_
 data More...
 
short whichWay_
 Computed preferred way to branch. More...
 
short numberWays_
 Maximum number of ways on branch. More...
 
int priority_
 Priority. More...
 

Detailed Description

Branching object for cliques.

A clique is defined to be a set of binary variables where fixing any one variable to its `strong' value fixes all other variables. An example is the most common SOS1 construction: a set of binary variables x_j s.t. SUM{j} x_j = 1. Setting any one variable to 1 forces all other variables to 0. (See comments for CbcSOS below.)

Other configurations are possible, however: Consider x1-x2+x3 <= 0. Setting x1 (x3) to 1 forces x2 to 1 and x3 (x1) to 0. Setting x2 to 0 forces x1 and x3 to 0.

The proper point of view to take when interpreting CbcClique is `generalisation of SOS1 on binary variables.' To get into the proper frame of mind, here's an example.

Consider the following sequence, where x_j = (1-y_j):

   x1 + x2 + x3 <=  1           all strong at 1
   x1 - y2 + x3 <=  0           y2 strong at 0; x1, x3 strong at 1
  -y1 - y2 + x3 <= -1           y1, y2 strong at 0, x3 strong at 1
  -y1 - y2 - y3 <= -2           all strong at 0

The first line is a standard SOS1 on binary variables.

Variables with +1 coefficients are `SOS-style' and variables with -1 coefficients are `non-SOS-style'. So numberNonSOSMembers_ simply tells you how many variables have -1 coefficients. The implicit rhs for a clique is 1-numberNonSOSMembers_.

Definition at line 41 of file CbcClique.hpp.

Constructor & Destructor Documentation

CbcClique::CbcClique ( )

Default Constructor.

CbcClique::CbcClique ( CbcModel model,
int  cliqueType,
int  numberMembers,
const int *  which,
const char *  type,
int  identifier,
int  slack = -1 
)

Useful constructor (which are integer indices) slack can denote a slack in set.

If type == NULL then as if 1

CbcClique::CbcClique ( const CbcClique )

Copy constructor.

virtual CbcClique::~CbcClique ( )
virtual

Destructor.

Member Function Documentation

virtual CbcObject* CbcClique::clone ( ) const
virtual

Clone.

Implements CbcObject.

CbcClique& CbcClique::operator= ( const CbcClique rhs)

Assignment operator.

virtual double CbcClique::infeasibility ( const OsiBranchingInformation info,
int &  preferredWay 
) const
virtual

Infeasibility - large is 0.5.

Reimplemented from CbcObject.

virtual void CbcClique::feasibleRegion ( )
virtual

This looks at solution and sets bounds to contain solution.

Implements CbcObject.

virtual CbcBranchingObject* CbcClique::createCbcBranch ( OsiSolverInterface solver,
const OsiBranchingInformation info,
int  way 
)
virtual

Creates a branching object.

Reimplemented from CbcObject.

int CbcClique::numberMembers ( ) const
inline

Number of members.

Definition at line 78 of file CbcClique.hpp.

int CbcClique::numberNonSOSMembers ( ) const
inline

Number of variables with -1 coefficient.

Number of non-SOS members, i.e., fixing to zero is strong. See comments at head of class, and comments for type_.

Definition at line 86 of file CbcClique.hpp.

const int* CbcClique::members ( ) const
inline

Members (indices in range 0 ... numberIntegers_-1)

Definition at line 91 of file CbcClique.hpp.

char CbcClique::type ( int  index) const
inline

Type of each member, i.e., which way is strong.

This also specifies whether a variable has a +1 or -1 coefficient.

  • 0 => -1 coefficient, 0 is strong value
  • 1 => +1 coefficient, 1 is strong value If unspecified, all coefficients are assumed to be positive.

Indexed as 0 .. numberMembers_-1

Definition at line 104 of file CbcClique.hpp.

int CbcClique::cliqueType ( ) const
inline

Clique type: 0 is <=, 1 is ==.

Definition at line 110 of file CbcClique.hpp.

virtual void CbcClique::redoSequenceEtc ( CbcModel model,
int  numberColumns,
const int *  originalColumns 
)
virtual

Redoes data when sequence numbers change.

Reimplemented from CbcObject.

Member Data Documentation

int CbcClique::numberMembers_
protected

data Number of members

Definition at line 119 of file CbcClique.hpp.

int CbcClique::numberNonSOSMembers_
protected

Number of Non SOS members i.e. fixing to zero is strong.

Definition at line 122 of file CbcClique.hpp.

int* CbcClique::members_
protected

Members (indices in range 0 ... numberIntegers_-1)

Definition at line 125 of file CbcClique.hpp.

char* CbcClique::type_
protected

Strong value for each member.

This also specifies whether a variable has a +1 or -1 coefficient.

  • 0 => -1 coefficient, 0 is strong value
  • 1 => +1 coefficient, 1 is strong value If unspecified, all coefficients are assumed to be positive.

Indexed as 0 .. numberMembers_-1

Definition at line 136 of file CbcClique.hpp.

int CbcClique::cliqueType_
protected

Clique type.

0 defines a <= relation, 1 an equality. The assumed value of the rhs is numberNonSOSMembers_+1. (See comments for the class.)

Definition at line 143 of file CbcClique.hpp.

int CbcClique::slack_
protected

Slack variable for the clique.

Identifies the slack variable for the clique (typically added to convert a <= relation to an equality). Value is sequence number within clique menbers.

Definition at line 151 of file CbcClique.hpp.


The documentation for this class was generated from the following file: