In file ../include/EST_SCFG.h:

class EST_SCFG_Rule

A stochastic context free grammar rule.

Public Methods

	EST_SCFG_Rule ()
	EST_SCFG_Rule (const EST_SCFG_Rule &r)
	EST_SCFG_Rule (double prob, int p, int m) Create a unary rule
	EST_SCFG_Rule (double prob, int p, int q, int r) Create a binary rule
double	prob () const The rule's probability
void	set_prob (double p) set the probability
est_scfg_rtype	type () const rule type
int	mother () const
int	daughter1 () const In a unary rule this is a terminal, in a binary rule it is a nonterminal
int	daughter2 () const
void	set_rule (double prob, int p, int m)
void	set_rule (double prob, int p, int q, int r)

Documentation

A stochastic context free grammar rule.

At present only two types of rule are supported: est_scfg_binary_rule and est_scfg_unary_rule. This is sufficient for the representation of grammars in Chomsky Normal Form. Each rule also has a probability associated with it. Terminals and noterminals are represented as ints using the EST_Discretes in EST_SCFG to reference the actual alphabets.

Although this class includes a ``probability'' nothing in the rule itself enforces it to be a true probability. It is responsibility of the classes that use this rule to enforce that condition if desired.

EST_SCFG_Rule()

EST_SCFG_Rule(const EST_SCFG_Rule &r)

EST_SCFG_Rule(double prob, int p, int m)

Create a unary rule

EST_SCFG_Rule(double prob, int p, int q, int r)

Create a binary rule

double prob() const

The rule's probability

void set_prob(double p)

set the probability

est_scfg_rtype type() const

rule type

int mother() const

int daughter1() const

In a unary rule this is a terminal, in a binary rule it is a nonterminal

int daughter2() const

void set_rule(double prob, int p, int m)

void set_rule(double prob, int p, int q, int r)

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