The basic class for computing the next graph changes possible in a structure learning algorithm. More...

#include <graphChangesGenerator4DiGraph.h>

Inheritance diagram for gum::learning::GraphChangesGenerator4DiGraph< STRUCT_CONSTRAINT >:

Collaboration diagram for gum::learning::GraphChangesGenerator4DiGraph< STRUCT_CONSTRAINT >:

Public Member Functions
Constructors / Destructors
	GraphChangesGenerator4DiGraph (STRUCT_CONSTRAINT &constraint)
	default constructor More...

	GraphChangesGenerator4DiGraph (const GraphChangesGenerator4DiGraph< STRUCT_CONSTRAINT > &from)
	copy constructor More...

	GraphChangesGenerator4DiGraph (GraphChangesGenerator4DiGraph< STRUCT_CONSTRAINT > &&from)
	move operator More...

virtual	~GraphChangesGenerator4DiGraph ()
	destructor More...

Operators
GraphChangesGenerator4DiGraph< STRUCT_CONSTRAINT > &	operator= (const GraphChangesGenerator4DiGraph< STRUCT_CONSTRAINT > &from)
	copy operator More...

GraphChangesGenerator4DiGraph< STRUCT_CONSTRAINT > &	operator= (GraphChangesGenerator4DiGraph< STRUCT_CONSTRAINT > &&from)
	move operator More...

Iterators
iterator	begin () const
	returns an (unsafe) iterator on the beginning of the list of operators More...

const iterator &	end () const
	returns an (unsafe) iterator on the end of the list of operators More...

Accessors / Modifiers
STRUCT_CONSTRAINT &	constraint () const noexcept
	returns the constraint that is used by the generator More...

void	setGraph (const DiGraph &graph)
	sets a new graph from which the generator will compute possible changes More...

void	modifyGraph (const ArcAddition &change)
	notify the generator of a change applied to the graph More...

void	modifyGraph (const ArcDeletion &change)
	notify the generator of a change applied to the graph More...

void	modifyGraph (const ArcReversal &change)
	notify the generator of a change applied to the graph More...

void	modifyGraph (const GraphChange &change)
	notify the generator of a change applied to the graph More...

void	clearChanges () noexcept
	empty the set of possible change operators that can be applied More...

void	notifyGetCompleted ()
	notifies the generator that we have parsed all its legal changes More...

void	setMaxNbThreads (Size nb) noexcept
	sets the maximum number of threads used to compute the set of changes More...

Public Types
using	iterator = typename Set< GraphChange >::const_iterator
	the iterator for parsing the list of possible graph change operators More...

using	const_iterator = iterator
	the const iterator for parsing the list of graph change operators More...

Protected Attributes
DiGraph	graph_
	the graph on which we generate operators More...

STRUCT_CONSTRAINT *	constraint_
	the structural constraint used to restrict the changes More...

Set< GraphChange >	legal_changes_
	the current set of graph changes More...

Protected Member Functions
void	createChanges_ ()
	create the set of legal and illegal changes from a given graph More...

Detailed Description

template<typename STRUCT_CONSTRAINT>
class gum::learning::GraphChangesGenerator4DiGraph< STRUCT_CONSTRAINT >

The basic class for computing the next graph changes possible in a structure learning algorithm.

Structure learning algorithm try different modifications of the graph. Class GraphChangesGenerator4DiGraph provides a simple way to compute those that we wish to perform. For instance, in the basic LocalSearch algorithm for learning directed graphs, one may expect that all possible arc additions, deletions and reversals can be applied and GraphChangesGenerator4DiGraph provides exactly this set of operations. However, there may be cases where we would like to apply these operators, say, only on a subgraph. In this case, we should use the derived class of GraphChangesGenerator4DiGraph named GraphChangesGeneratorOnSubDiGraph. Anyway, all the search generators should have the following minimal methods:

void setGraph ( const DiGraph& ) : assigns a new graph as a starting point to the generator of graph change operators
void modifyGraph ( const GraphChange& ) : indicate to the generator that the graph has been changed and that we need to compute the new operators that result from this change
void clearChanges () : empty the set of possible changes
methods begin () and end () that return iterators allowing to parse the available set of changes.

Basically, the idea is to use method setGraph at the beginning of the structure learning in order to initialize the possible set of changes. Then, parse this set using a for ( auto iter = generator.begin (); iter != generator.end (); ++iter ) loop and compute the scores induced by these changes. When this is done, flush the generator by calling method clearChanges. Then iterate changes and after each new change applied, used again the iterator for loop, and so on. Note that, whenever you execute method modifyGraph, this will automatically flush the current list of changes and put into the list only the changes that are affected by the graph modification.

Definition at line 116 of file graphChangesGenerator4DiGraph.h.