nltk.ccg.CCGLeafEdge

class nltk.ccg.CCGLeafEdge

Bases: EdgeI

Class representing leaf edges in a CCG derivation.

__init__(pos, token, leaf)

lhs()

Return this edge’s left-hand side, which specifies what kind of structure is hypothesized by this edge.

See

TreeEdge and LeafEdge for a description of the left-hand side values for each edge type.

span()

Return a tuple (s, e), where tokens[s:e] is the portion of the sentence that is consistent with this edge’s structure.

Return type

tuple(int, int)

start()

Return the start index of this edge’s span.

Return type

int

end()

Return the end index of this edge’s span.

Return type

int

length()

Return the length of this edge’s span.

Return type

int

rhs()

Return this edge’s right-hand side, which specifies the content of the structure hypothesized by this edge.

See

TreeEdge and LeafEdge for a description of the right-hand side values for each edge type.

dot()

Return this edge’s dot position, which indicates how much of the hypothesized structure is consistent with the sentence. In particular, self.rhs[:dot] is consistent with tokens[self.start():self.end()].

Return type

int

is_complete()

Return True if this edge’s structure is fully consistent with the text.

Return type

bool

is_incomplete()

Return True if this edge’s structure is partially consistent with the text.

Return type

bool

nextsym()

Return the element of this edge’s right-hand side that immediately follows its dot.

Return type

Nonterminal or terminal or None

token()

categ()

leaf()