Package de.saar.chorus.domgraph.chart

Class OneSplitSource

java.lang.Object

de.saar.chorus.domgraph.chart.SplitSource<SubgraphNonterminal>

de.saar.chorus.domgraph.chart.OneSplitSource

public class OneSplitSource
extends SplitSource<SubgraphNonterminal>

A split source which only computes the first split for each subgraph. A ChartSolver which uses a split source of this class will not compute the complete set of solved forms. However, it is still guaranteed to detect whether a graph is unsolvable, and will be considerably faster than a solver that uses a CompleteSplitSource.

Author:

Alexander Koller

Field Summary

Fields inherited from class de.saar.chorus.domgraph.chart.SplitSource

graph

Constructor Summary

Constructors

Constructor	Description
OneSplitSource(DomGraph graph)

Method Summary

Modifier and Type	Method	Description
Iterator<Split<SubgraphNonterminal>>	computeSplits(SubgraphNonterminal subgraph)	Implement this abstract method when you write your own subclass of SplitSource.
static boolean	isGraphSolvable(DomGraph graph)
SubgraphNonterminal	makeToplevelSubgraph(Set<String> graph)
void	reduceIfNecessary(ConcreteRegularTreeGrammar<SubgraphNonterminal> chart)	Reduces the computed RTG.

Methods inherited from class de.saar.chorus.domgraph.chart.SplitSource

computePotentialFreeRoots, getGraph

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Details

OneSplitSource

public OneSplitSource(DomGraph graph)

Method Details

computeSplits

public Iterator<Split<SubgraphNonterminal>> computeSplits(SubgraphNonterminal subgraph)
                                                   throws UnsolvableSubgraphException

Description copied from class: SplitSource

Implement this abstract method when you write your own subclass of SplitSource. The method gets a subgraph as its argument, and has the task of computing an iterator over the splits of this subgraph.

Specified by:

computeSplits in class SplitSource<SubgraphNonterminal>

Parameters:

subgraph - a subgraph

Returns:

an iterator over some or all splits of this subgraph

Throws:

UnsolvableSubgraphException

isGraphSolvable

public static boolean isGraphSolvable(DomGraph graph)
                               throws SolverNotApplicableException

Throws:

SolverNotApplicableException

makeToplevelSubgraph

public SubgraphNonterminal makeToplevelSubgraph(Set<String> graph)

Specified by:

makeToplevelSubgraph in class SplitSource<SubgraphNonterminal>

reduceIfNecessary

public void reduceIfNecessary(ConcreteRegularTreeGrammar<SubgraphNonterminal> chart)

Description copied from class: SplitSource

Reduces the computed RTG. If your split source is such that the RTG it computes is not automatically reduced, you should implement this method to call reduce() on the output RTG. This method is called as the last operation by the chart solver.

Specified by:

reduceIfNecessary in class SplitSource<SubgraphNonterminal>

Parameters:

chart - the output RTG computed by the chart solver