A more elaborate diving class. More...

#include <BonDiver.hpp>

Public Types
enum	ComparisonModes { Enlarge, FindSolutions, CloseBound, LimitTreeSize }
Public Member Functions
	CbcDfsDiver ()
	Default constructor.
	CbcDfsDiver (const CbcDfsDiver &rhs)
	Copy constructor.
CbcDfsDiver &	operator= (const CbcDfsDiver &rhs)
	Assignment operator.
virtual	~CbcDfsDiver ()
	Destructor.
virtual CbcTree *	clone () const
	Virtual copy constructor.
virtual void	cleanTree (CbcModel *model, double cutoff, double &bestPossibleObjective)
	Prune the tree using an objective function cutoff.
virtual double	getBestPossibleObjective ()
	Get best possible objective function in the tree.
void	initialize (BabSetupBase &b)
	Initialize the method (get options)
virtual void	endSearch ()
	Don't know what this is yet?
void	setComparisonMode (ComparisonModes newMode)
	Changes the mode of comparison of the tree for "safety reasons" if the mode really changes we always finish the current dive and put all the node back onto the heap.
ComparisonModes	getComparisonMode ()
	get the mode of comparison of the tree.
Heap access and maintenance methods.
virtual CbcNode *	top () const
	Return top node (next node to process.*/.
virtual void	push (CbcNode *x)
	Add node to the heap.
virtual void	pop ()
	Remove the top node of the heap.
virtual CbcNode *	bestNode (double cutoff)
	Remove the best node from the heap and return it.
vector methods
virtual bool	empty ()
	Test if empty.
virtual int	size ()
	Give size of the tree.
Static Public Member Functions
static void	registerOptions (Ipopt::SmartPtr< Bonmin::RegisteredOptions > roptions)
	Register the options of the method.
Protected Attributes
int	treeCleaning_
	Flag to say that we are currently cleaning the tree and should work only on the heap.
std::list< CbcNode * >	dive_
	List of the nodes in the current dive.
int	diveListSize_
	Record dive list size for constant time access.
int	divingBoardDepth_
	Depth of the node from which diving was started (we call this node the diving board).
double	cutoff_
	Last reported cutoff.
int	nBacktracks_
	number of backtracks done in current dive.
Parameters of the method.
int	maxDepthBFS_
	Maximum depth until which we'll do a bredth-first-search.
int	maxDiveBacktracks_
	Maximum number of backtrack in one dive.
int	maxDiveDepth_
	Maximum depth to go from divingBoard.
ComparisonModes	mode_
	Current mode of the diving strategy.
Private Member Functions
void	pushDiveOntoHeap (double cutoff)
	Pushes onto heap all the nodes with objective value > cutoff.

Detailed Description

A more elaborate diving class.

First there are several modes which can be commanded by the Comparison class below. In particular can command to dive to find solutions, to try to close the bound as possible or to limit the size of the tree.

The diving goes into the tree doing depth-first search until one of the following happens:

A prescibed maxDiveBacktrack_ number of backtracking are performed.
The guessed objective value of the current node is worst than the best incumbent.
The depth of the dive is bigger than maxDiveDepth_

In the first case all the nodes are put on the tree and the next node on top will be the top of the heap, in the two latter case we just put the node on the tree and backtrack in the list of depth-first search nodes.

Bug:: This won't work in a non-convex problem where objective does not decrease down branches.

Definition at line 199 of file BonDiver.hpp.

Member Enumeration Documentation

enum Bonmin::CbcDfsDiver::ComparisonModes

Enumerator:

Enlarge	At the very beginning we might want to enlarge the tree just a bit.
FindSolutions
CloseBound
LimitTreeSize

Definition at line 202 of file BonDiver.hpp.

Constructor & Destructor Documentation

Bonmin::CbcDfsDiver::CbcDfsDiver ( )

Default constructor.

Bonmin::CbcDfsDiver::CbcDfsDiver ( const CbcDfsDiver & rhs )

Copy constructor.

virtual Bonmin::CbcDfsDiver::~CbcDfsDiver ( ) [virtual]

Destructor.

Member Function Documentation

CbcDfsDiver& Bonmin::CbcDfsDiver::operator= ( const CbcDfsDiver & rhs )

Assignment operator.

virtual CbcTree* Bonmin::CbcDfsDiver::clone ( ) const [virtual]

Virtual copy constructor.

virtual CbcNode* Bonmin::CbcDfsDiver::top ( ) const [virtual]

Return top node (next node to process.*/.

virtual void Bonmin::CbcDfsDiver::push ( CbcNode * x ) [virtual]

Add node to the heap.

virtual void Bonmin::CbcDfsDiver::pop ( ) [virtual]

Remove the top node of the heap.

virtual CbcNode* Bonmin::CbcDfsDiver::bestNode ( double cutoff ) [virtual]

Remove the best node from the heap and return it.

virtual bool Bonmin::CbcDfsDiver::empty ( ) [virtual]

Test if empty.

virtual int Bonmin::CbcDfsDiver::size ( ) [inline, virtual]

Give size of the tree.

Definition at line 240 of file BonDiver.hpp.

References diveListSize_.

virtual void Bonmin::CbcDfsDiver::cleanTree	(	CbcModel *	model,
		double	cutoff,
		double &	bestPossibleObjective
	)		`[virtual]`

Prune the tree using an objective function cutoff.

This routine removes all nodes with objective worst than the specified cutoff value. It also sets bestPossibleObjective to best of all on tree before deleting.

Bug:: This won't work in a non-convex problem where objective does not decrease down branches.

virtual double Bonmin::CbcDfsDiver::getBestPossibleObjective ( ) [virtual]

Get best possible objective function in the tree.

static void Bonmin::CbcDfsDiver::registerOptions ( Ipopt::SmartPtr< Bonmin::RegisteredOptions > roptions ) [static]

Register the options of the method.

void Bonmin::CbcDfsDiver::initialize ( BabSetupBase & b )

Initialize the method (get options)

virtual void Bonmin::CbcDfsDiver::endSearch ( ) [inline, virtual]

Don't know what this is yet?

Definition at line 267 of file BonDiver.hpp.

void Bonmin::CbcDfsDiver::setComparisonMode ( ComparisonModes newMode )

Changes the mode of comparison of the tree for "safety reasons" if the mode really changes we always finish the current dive and put all the node back onto the heap.

ComparisonModes Bonmin::CbcDfsDiver::getComparisonMode ( ) [inline]

get the mode of comparison of the tree.

Definition at line 274 of file BonDiver.hpp.

References mode_.

void Bonmin::CbcDfsDiver::pushDiveOntoHeap ( double cutoff ) [private]

Pushes onto heap all the nodes with objective value > cutoff.