nltk.sem.drt.DRS

class documentation

class DRS(DrtExpression, Expression): (source)

Constructor: DRS(refs, conds, consequent)

View In Hierarchy

A Discourse Representation Structure.

Method __eq__ Defines equality modulo alphabetic variance. If we are comparing x.M and y.N, then check equality of M and N[x/y].
Method __init__ discourse referents :param conds: list of Expression for the conditions
Method __ne__ Undocumented
Method __str__ Undocumented
Method eliminate_equality Undocumented
Method fol Undocumented
Method free No summary
Method get_refs No summary
Method replace Replace all instances of variable v with expression E in self, where v is free in self.
Method visit No summary
Method visit_structured No summary
Instance Variable conds Undocumented
Instance Variable consequent Undocumented
Instance Variable refs Undocumented
Method _order_ref_strings Undocumented
Method _pretty Undocumented

Inherited from DrtExpression:

Class Method fromstring Undocumented
Method __add__ Undocumented
Method __and__ Undocumented
Method __gt__ Undocumented
Method __neg__ Undocumented
Method __or__ Undocumented
Method applyto Undocumented
Method draw Undocumented
Method equiv Check for logical equivalence. Pass the expression (self <-> other) to the theorem prover. If the prover says it is valid, then the self and other are equal.
Method is_pronoun_function Is self of the form "PRO(x)"?
Method make_EqualityExpression Undocumented
Method make_VariableExpression Undocumented
Method pretty_format Draw the DRS :return: the pretty print string
Method pretty_print Undocumented
Method resolve_anaphora Undocumented
Method typecheck Undocumented
Property type Undocumented
Class Variable _drt_parser Undocumented

Inherited from Expression (via DrtExpression):

Method __call__ Undocumented
Method __hash__ Undocumented
Method __lt__ Undocumented
Method __repr__ Undocumented
Method constants Return a set of individual constants (non-predicates). :return: set of Variable objects
Method findtype Find the type of the given variable as it is used in this expression. For example, finding the type of "P" in "P(x) & Q(x,y)" yields "<e,t>"
Method negate If this is a negated expression, remove the negation. Otherwise add a negation.
Method normalize Rename auto-generated unique variables
Method predicates Return a set of predicates (constants, not variables). :return: set of Variable objects
Method simplify No summary
Method substitute_bindings No summary
Method variables Return a set of all the variables for binding substitution. The variables returned include all free (non-bound) individual variables and any variable starting with '?' or '@'. :return: set of Variable objects...
Method _set_type Set the type of this expression to be the given type. Raise type exceptions where applicable.
Class Variable _logic_parser Undocumented
Class Variable _type_checking_logic_parser Undocumented
def __eq__(self, other): (source)
overrides nltk.sem.logic.Expression.__eq__

Defines equality modulo alphabetic variance. If we are comparing x.M and y.N, then check equality of M and N[x/y].

def __init__(self, refs, conds, consequent=None): (source)

discourse referents :param conds: list of Expression for the conditions

Parameters
refslist of DrtIndividualVariableExpression for the
condsUndocumented
consequentUndocumented
def __ne__(self, other): (source)
overrides nltk.sem.logic.Expression.__ne__

Undocumented

def __str__(self): (source)
overrides nltk.sem.logic.Expression.__str__

Undocumented

def eliminate_equality(self): (source)
overrides nltk.sem.drt.DrtExpression.eliminate_equality

Undocumented

def fol(self): (source)

Undocumented

def free(self): (source)
overrides nltk.sem.logic.Expression.free
See Also
Expression.free()
def get_refs(self, recursive=False): (source)
overrides nltk.sem.drt.DrtExpression.get_refs
See Also
AbstractExpression.get_refs()
def replace(self, variable, expression, replace_bound=False, alpha_convert=True): (source)
overrides nltk.sem.logic.Expression.replace

Replace all instances of variable v with expression E in self, where v is free in self.

def visit(self, function, combinator): (source)
overrides nltk.sem.logic.Expression.visit
See Also
Expression.visit()
def visit_structured(self, function, combinator): (source)
overrides nltk.sem.logic.Expression.visit_structured
See Also
Expression.visit_structured()
conds = (source)

Undocumented

consequent = (source)

Undocumented

refs = (source)

Undocumented

def _order_ref_strings(self, refs): (source)

Undocumented

def _pretty(self): (source)

Undocumented