In file ../include/EST_SCFG_Chart.h:

class EST_SCFG_Chart

A class for parsing with a probabalistic grammars.

Public Methods

Grammar and parse string initialisation functions void set_grammar_rules (LISP r) Initialize from LISP rules set void set_grammar_rules (EST_SCFG &grammar) Initialize from existing EST_SCFG grammar void setup_wfst (EST_Relation* s, const EST_String &name="name") Initialize for parsing from relation using name feature setting up the "Well Fromed Substring Table" void setup_wfst (EST_Item* s, EST_Item* e, const EST_String &name="name") Initialize for parsing from s to e using name feature setting up the "Well Fromed Substring Table"

parsing functions void parse () Parses the loaded WFST with the loaded grammar LISP find_parse () Return the parse in full LISP form void extract_parse (EST_Relation* syn, EST_Relation* word, int force=0) Extract parse tree and add it to syn linking leafs to word void extract_parse (EST_Relation* syn, EST_Item* s, EST_Item* e, int force=0) Extract parse tree and add it to syn linking leafs to items s to e

Documentation

A class for parsing with a probabalistic grammars.

The chart (sort of closer to CKY table) consists of indexes of edges indexed by vertex number of mother non-terminal.

The initial values (well-formed substring table) are taken from an EST_Stream with a given feature. The grammar may be specified as LISP rules or as an already constructed EST_SCFG.

This produces a single best parse. It treates the grammar as structly context free in that the probability of a nonterminal over vertex n to m, is the sum of the all possible analysis of that sub-tree. Only the best anaylsis is kept for the resulting parse tree.

Constructor and initialisation functions

Grammar and parse string initialisation functions

void set_grammar_rules(LISP r)

Initialize from LISP rules set

void set_grammar_rules(EST_SCFG &grammar)

Initialize from existing EST_SCFG grammar

void setup_wfst(EST_Relation* s, const EST_String &name="name")

Initialize for parsing from relation using name feature setting up the "Well Fromed Substring Table"

void setup_wfst(EST_Item* s, EST_Item* e, const EST_String &name="name")

Initialize for parsing from s to e using name feature setting up the "Well Fromed Substring Table"

parsing functions

void parse()

Parses the loaded WFST with the loaded grammar

LISP find_parse()

Return the parse in full LISP form

void extract_parse(EST_Relation* syn, EST_Relation* word, int force=0)

Extract parse tree and add it to syn linking leafs to word

void extract_parse(EST_Relation* syn, EST_Item* s, EST_Item* e, int force=0)

Extract parse tree and add it to syn linking leafs to items s to e

This class has no child classes.

Author:

Alan W Black (awb@cstr.ed.ac.uk): October 1997

Alphabetic index HTML hierarchy of classes or Java

This page is part of the Edinburgh Speech Tools Library documentation
Copyright University of Edinburgh 1997
Contact: speech_tools@cstr.ed.ac.uk