Type InsideParse
object
--+
|
ParseI
--+
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AbstractParse
--+
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BottomUpChartParse
--+
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InsideParse
A bottom-up parser for PCFG
s that tries edges in
descending order of the inside probabilities of their trees. The inside
probability of a tree is simply the probability of the entire tree,
ignoring its context. In particular, the inside probability of a tree
generated by production p with children c[1], c[2], ..., c[n] is P(p)*P(c[1])*P(c[2])*...*P(c[n]); and the inside
probability of a token is 1 if it is present in the text, and 0 if it is
absent.
This sorting order results in a type of lowest-cost-first search
strategy.
Method Summary |
None
|
sort_queue (self,
queue,
chart)
Sort the given queue of edges, in descending order of the inside
probabilities of the edges' trees. |
Inherited from BottomUpChartParse :
__init__ ,
get_parse_list ,
trace ,
_setprob
Inherited from AbstractParse :
get_parse ,
grammar ,
parse
Inherited from ParseI :
get_parse_probs
Inherited from object :
__delattr__ ,
__getattribute__ ,
__hash__ ,
__new__ ,
__reduce__ ,
__reduce_ex__ ,
__repr__ ,
__setattr__ ,
__str__
|
sort_queue(self,
queue,
chart)
Sort the given queue of edges, in descending order of the inside
probabilities of the edges' trees.
-
- Parameters:
queue -
The queue of Edge s to sort. Each edge in this
queue is an edge that could be added to the chart by the
fundamental rule; but that has not yet been added.
(type=list of Edge )
chart -
The chart being used to parse the text. This chart can be used
to provide extra information for sorting the queue.
(type=Chart )
- Returns:
-
None
- Overrides:
nltk_lite.parse.pchart.BottomUpChartParse.sort_queue
|