nltk.parse.earleychart.IncrementalChartParser

type IncrementalChartParser

object --+ | api.ParserI --+ | chart.ChartParser --+ | IncrementalChartParser

An incremental chart parser implementing Jay Earley's parsing algorithm:

For each index end in [0, 1, ..., N]:

For each edge s.t. edge.end = end:
- If edge is incomplete, and edge.next is not a part of speech:
  - Apply PredictorRule to edge
- If edge is incomplete, and edge.next is a part of speech:
  - Apply ScannerRule to edge
- If edge is complete:
  - Apply CompleterRule to edge

Return any complete parses in the chart

Instance Methods

__init__(self, grammar, strategy=BU_LC_INCREMENTAL_STRATEGY, trace=0, trace_chart_width=50, chart_class=<class 'nltk.parse.earleychart.IncrementalChart'>)
Create a new Earley chart parser, that uses grammar to parse texts. source code

Chart

chart_parse(self, tokens, trace=None)
Returns: The final parse Chart, from which all possible parse trees can be extracted.

source code

Inherited from chart.ChartParser: grammar, nbest_parse

Inherited from chart.ChartParser (private): _trace_new_edges

Inherited from api.ParserI: batch_iter_parse, batch_nbest_parse, batch_parse, batch_prob_parse, iter_parse, parse, prob_parse

Deprecated

Inherited from api.ParserI: batch_test, get_parse, get_parse_dict, get_parse_list, get_parse_prob

init(self, grammar, strategy=BU_LC_INCREMENTAL_STRATEGY, trace=0, trace_chart_width=50, chart_class=<class 'nltk.parse.earleychart.IncrementalChart'>)
(Constructor)

source code

Create a new Earley chart parser, that uses grammar to parse texts.

Parameters:

grammar (ContextFreeGrammar) - The grammar used to parse texts.
trace (int) - The level of tracing that should be used when parsing a text. 0 will generate no tracing output; and higher numbers will produce more verbose tracing output.
trace_chart_width (int) - The default total width reserved for the chart in trace output. The remainder of each line will be used to display edges.
chart_class - The class that should be used to create the charts used by this parser.

Overrides: chart.ChartParser.__init__

chart_parse(self, tokens, trace=None)

source code

Parameters:

tokens - The sentence to be parsed

Returns: Chart

The final parse Chart, from which all possible parse trees can be extracted.

Overrides: chart.ChartParser.chart_parse

(inherited documentation)

type IncrementalChartParser

__init__(self, grammar, strategy=BU_LC_INCREMENTAL_STRATEGY, trace=0, trace_chart_width=50, chart_class=<class 'nltk.parse.earleychart.IncrementalChart'>) (Constructor)

chart_parse(self, tokens, trace=None)

init(self, grammar, strategy=BU_LC_INCREMENTAL_STRATEGY, trace=0, trace_chart_width=50, chart_class=<class 'nltk.parse.earleychart.IncrementalChart'>)
(Constructor)