Package nltk :: Package parse :: Module chart :: Class SingleEdgeFundamentalRule

type SingleEdgeFundamentalRule

   object --+            
            |            
   ChartRuleI --+        
                |        
AbstractChartRule --+    
                    |    
      FundamentalRule --+
                        |
                       SingleEdgeFundamentalRule

Known Subclasses:

A rule that joins a given edge with adjacent edges in the chart, to form combined edges. In particular, this rule specifies that either of the edges:

[A → α * B β][i:j]
[B → γ *][j:k]

licenses the edge:

[A → α B * β][i:j]

if the other edge is already in the chart.

Note: This is basically FundamentalRule, with one edge left unspecified.

Instance Methods

[hide private]

iter of EdgeI

apply_iter(self, chart, grammar, edge)
Returns: A generator that will add edges licensed by this rule and the given edges to the chart, one at a time.

source code

_apply_complete(self, chart, grammar, right_edge)

source code

_apply_incomplete(self, chart, grammar, left_edge)

source code

Inherited from AbstractChartRule: __str__, apply, apply_everywhere, apply_everywhere_iter

Class Variables

[hide private]

int NUM_EDGES = 1
The number of existing edges that this rule uses to license new edges.

Method Details

[hide private]

apply_iter(self, chart, grammar, edge)

source code

Parameters:

edges - A set of existing edges. The number of edges that should be passed to apply is specified by the NUM_EDGES class variable.

Returns: iter of EdgeI

A generator that will add edges licensed by this rule and the given edges to the chart, one at a time. Each time the generator is resumed, it will either add a new edge and yield that edge; or return.

Overrides: ChartRuleI.apply_iter

(inherited documentation)