Package parser_course :: Package small_parsers :: Module very_simple_cky_parser :: Class CKYParser

Class CKYParser

small_parser.SmallParser --+
                           |
                          CKYParser

Parse strings in self.data using CKY algorithm (see SmallParser methods too):

To create CKYParser instance p1 with grammar g1: p1 = CKYParser(g1) To find edge(mother_cat,start,end) (after parsing!):

           p1.find_parse_edge(end, start,mother_cat)

To pretty print all parse trees after parsing:

           p1.print_nltk_parses()

To draw all parse trees after parsing (in fancy graphix window):

           p1.draw_nltk_parses()

To draw all parses for edge(mother_cat,start,end) (after parsing!):

       p1.draw_nltk_parse_trees_for_edge (self,end,start,mother_cat)

Instance Methods

[hide private]

initialize_chart(self)

source code

process(self)
Abstract method.

source code

add_to_chart(self, end, start, mother_cat, dtrs)

source code

add_lexical_edge(self, cat, j)

source code

update_dtr_records(self, len, start, cat, dtrs)

source code

find_parse_edge(self, end, start, mother_cat)
Retrieve unique edge matching description from chart.

source code

find_spanning_edge(self)
Abstract method: Shd be defined to return a spanning edge from which dtr edges can be recursively retrieved from self.dtr_dict

source code

matching_edge(self, edge_info)
Return True if edge matching edge_info triple exists in chart.

source code

display_chart(self)
Abstract method: Shd be defined with parser-specific print methods to print each edge in the chart.

source code

display_dtr_dict(self)

source code

draw_nltk_parse_trees_for_edge(self, end, start, mother_cat)

source code

_trace_print_binary_rule_(self, mother_cat, dtr_pair)

source code

_trace_print_unary_rule_(self, mother_cat, dtr)

source code

_trace_print_end_(self, end)

source code

_trace_print_start_(self, start, end)

source code

word_span(self, end, start)

source code

Inherited from small_parser.SmallParser: __init__, draw_list_parses, draw_nltk_parses, find_list_parses, find_nltk_parses, find_parses, get_list_parse_trees, get_nltk_parse_trees, parse_exists, parse_input, print_nltk_parses, reset_input, tex_output_parses, tokenize

Method Details

[hide private]

initialize_chart(self)

source code

Overrides: small_parser.SmallParser.initialize_chart

process(self)

source code

Abstract method. Implements a particular a particular chart parsing algorithm.

Overrides: small_parser.SmallParser.process: (inherited documentation)

find_parse_edge(self, end, start, mother_cat)

source code

Retrieve unique edge matching description from chart. Complete edge descriptions only.

find_spanning_edge(self)

source code

Abstract method: Shd be defined to return a spanning edge from which dtr edges can be recursively retrieved from self.dtr_dict

Overrides: small_parser.SmallParser.find_spanning_edge: (inherited documentation)

matching_edge(self, edge_info)

source code

Return True if edge matching edge_info triple exists in chart. Else return Fale.

display_chart(self)

source code

Abstract method: Shd be defined with parser-specific print methods to print each edge in the chart.

Overrides: small_parser.SmallParser.display_chart: (inherited documentation)