spaCy/spacy/syntax/ner.pyx

563 lines
18 KiB
Cython

from thinc.extra.search cimport Beam
from collections import Counter
from ..typedefs cimport weight_t
from .stateclass cimport StateClass
from ._state cimport StateC
from .transition_system cimport Transition
from .transition_system cimport do_func_t
from ..gold cimport GoldParseC, GoldParse
from ..lexeme cimport Lexeme
from ..attrs cimport IS_SPACE
from ..errors import Errors
cdef enum:
MISSING
BEGIN
IN
LAST
UNIT
OUT
ISNT
N_MOVES
MOVE_NAMES = [None] * N_MOVES
MOVE_NAMES[MISSING] = 'M'
MOVE_NAMES[BEGIN] = 'B'
MOVE_NAMES[IN] = 'I'
MOVE_NAMES[LAST] = 'L'
MOVE_NAMES[UNIT] = 'U'
MOVE_NAMES[OUT] = 'O'
MOVE_NAMES[ISNT] = 'x'
cdef do_func_t[N_MOVES] do_funcs
cdef bint _entity_is_sunk(StateClass st, Transition* golds) nogil:
if not st.entity_is_open():
return False
cdef const Transition* gold = &golds[st.E(0)]
if gold.move != BEGIN and gold.move != UNIT:
return True
elif gold.label != st.E_(0).ent_type:
return True
else:
return False
cdef class BiluoPushDown(TransitionSystem):
def __init__(self, *args, **kwargs):
TransitionSystem.__init__(self, *args, **kwargs)
@classmethod
def get_actions(cls, **kwargs):
actions = {
MISSING: Counter(),
BEGIN: Counter(),
IN: Counter(),
LAST: Counter(),
UNIT: Counter(),
OUT: Counter()
}
actions[OUT][''] = 1 # Represents a token predicted to be outside of any entity
actions[UNIT][''] = 1 # Represents a token prohibited to be in an entity
for entity_type in kwargs.get('entity_types', []):
for action in (BEGIN, IN, LAST, UNIT):
actions[action][entity_type] = 1
moves = ('M', 'B', 'I', 'L', 'U')
for example in kwargs.get('gold_parses', []):
for i, ner_tag in enumerate(example.token_annotation.entities):
if ner_tag != 'O' and ner_tag != '-':
_, label = ner_tag.split('-', 1)
for action in (BEGIN, IN, LAST, UNIT):
actions[action][label] += 1
return actions
@property
def action_types(self):
return (BEGIN, IN, LAST, UNIT, OUT)
def move_name(self, int move, attr_t label):
if move == OUT:
return 'O'
elif move == MISSING:
return 'M'
else:
return MOVE_NAMES[move] + '-' + self.strings[label]
def has_gold(self, GoldParse gold, start=0, end=None):
end = end or len(gold.ner)
if all([tag in ('-', None) for tag in gold.ner[start:end]]):
return False
else:
return True
def preprocess_gold(self, GoldParse gold):
if not self.has_gold(gold):
return None
for i in range(gold.length):
gold.c.ner[i] = self.lookup_transition(gold.ner[i])
return gold
def get_beam_annot(self, Beam beam):
entities = {}
probs = beam.probs
for i in range(beam.size):
state = <StateC*>beam.at(i)
if state.is_final():
self.finalize_state(state)
prob = probs[i]
for j in range(state._e_i):
start = state._ents[j].start
end = state._ents[j].end
label = state._ents[j].label
entities.setdefault((start, end, label), 0.0)
entities[(start, end, label)] += prob
return entities
def get_beam_parses(self, Beam beam):
parses = []
probs = beam.probs
for i in range(beam.size):
state = <StateC*>beam.at(i)
if state.is_final():
self.finalize_state(state)
prob = probs[i]
parse = []
for j in range(state._e_i):
start = state._ents[j].start
end = state._ents[j].end
label = state._ents[j].label
parse.append((start, end, self.strings[label]))
parses.append((prob, parse))
return parses
cdef Transition lookup_transition(self, object name) except *:
cdef attr_t label
if name == '-' or name == '' or name is None:
return Transition(clas=0, move=MISSING, label=0, score=0)
elif name == '!O':
return Transition(clas=0, move=ISNT, label=0, score=0)
elif '-' in name:
move_str, label_str = name.split('-', 1)
# Hacky way to denote 'not this entity'
if label_str.startswith('!'):
label_str = label_str[1:]
move_str = 'x'
label = self.strings.add(label_str)
else:
move_str = name
label = 0
move = MOVE_NAMES.index(move_str)
if move == ISNT:
return Transition(clas=0, move=ISNT, label=label, score=0)
for i in range(self.n_moves):
if self.c[i].move == move and self.c[i].label == label:
return self.c[i]
raise KeyError(Errors.E022.format(name=name))
cdef Transition init_transition(self, int clas, int move, attr_t label) except *:
# TODO: Apparent Cython bug here when we try to use the Transition()
# constructor with the function pointers
cdef Transition t
t.score = 0
t.clas = clas
t.move = move
t.label = label
if move == MISSING:
t.is_valid = Missing.is_valid
t.do = Missing.transition
t.get_cost = Missing.cost
elif move == BEGIN:
t.is_valid = Begin.is_valid
t.do = Begin.transition
t.get_cost = Begin.cost
elif move == IN:
t.is_valid = In.is_valid
t.do = In.transition
t.get_cost = In.cost
elif move == LAST:
t.is_valid = Last.is_valid
t.do = Last.transition
t.get_cost = Last.cost
elif move == UNIT:
t.is_valid = Unit.is_valid
t.do = Unit.transition
t.get_cost = Unit.cost
elif move == OUT:
t.is_valid = Out.is_valid
t.do = Out.transition
t.get_cost = Out.cost
else:
raise ValueError(Errors.E019.format(action=move, src='ner'))
return t
def add_action(self, int action, label_name, freq=None):
cdef attr_t label_id
if not isinstance(label_name, (int, long)):
label_id = self.strings.add(label_name)
else:
label_id = label_name
if action == OUT and label_id != 0:
return None
if action == MISSING or action == ISNT:
return None
# Check we're not creating a move we already have, so that this is
# idempotent
for trans in self.c[:self.n_moves]:
if trans.move == action and trans.label == label_id:
return 0
if self.n_moves >= self._size:
self._size = self.n_moves
self._size *= 2
self.c = <Transition*>self.mem.realloc(self.c, self._size * sizeof(self.c[0]))
self.c[self.n_moves] = self.init_transition(self.n_moves, action, label_id)
self.n_moves += 1
if self.labels.get(action, []):
freq = min(0, min(self.labels[action].values()))
self.labels[action][label_name] = freq-1
else:
self.labels[action] = Counter()
self.labels[action][label_name] = -1
return 1
cdef int initialize_state(self, StateC* st) nogil:
# This is especially necessary when we use limited training data.
for i in range(st.length):
if st._sent[i].ent_type != 0:
with gil:
self.add_action(BEGIN, st._sent[i].ent_type)
self.add_action(IN, st._sent[i].ent_type)
self.add_action(UNIT, st._sent[i].ent_type)
self.add_action(LAST, st._sent[i].ent_type)
cdef class Missing:
@staticmethod
cdef bint is_valid(const StateC* st, attr_t label) nogil:
return False
@staticmethod
cdef int transition(StateC* s, attr_t label) nogil:
pass
@staticmethod
cdef weight_t cost(StateClass s, const GoldParseC* gold, attr_t label) nogil:
return 9000
cdef class Begin:
@staticmethod
cdef bint is_valid(const StateC* st, attr_t label) nogil:
cdef int preset_ent_iob = st.B_(0).ent_iob
cdef attr_t preset_ent_label = st.B_(0).ent_type
# If we're the last token of the input, we can't B -- must U or O.
if st.B(1) == -1:
return False
elif st.entity_is_open():
return False
elif label == 0:
return False
elif preset_ent_iob == 1:
# Ensure we don't clobber preset entities. If no entity preset,
# ent_iob is 0
return False
elif preset_ent_iob == 3:
# Okay, we're in a preset entity.
if label != preset_ent_label:
# If label isn't right, reject
return False
elif st.B_(1).ent_iob != 1:
# If next token isn't marked I, we need to make U, not B.
return False
else:
# Otherwise, force acceptance, even if we're across a sentence
# boundary or the token is whitespace.
return True
elif st.B_(1).ent_iob == 3:
# If the next word is B, we can't B now
return False
elif st.B_(1).sent_start == 1:
# Don't allow entities to extend across sentence boundaries
return False
# Don't allow entities to start on whitespace
elif Lexeme.get_struct_attr(st.B_(0).lex, IS_SPACE):
return False
else:
return True
@staticmethod
cdef int transition(StateC* st, attr_t label) nogil:
st.open_ent(label)
st.set_ent_tag(st.B(0), 3, label)
st.push()
st.pop()
@staticmethod
cdef weight_t cost(StateClass s, const GoldParseC* gold, attr_t label) nogil:
cdef int g_act = gold.ner[s.B(0)].move
cdef attr_t g_tag = gold.ner[s.B(0)].label
if g_act == MISSING:
return 0
elif g_act == BEGIN:
# B, Gold B --> Label match
return label != g_tag
# Support partial supervision in the form of "not this label"
elif g_act == ISNT:
return label == g_tag
else:
# B, Gold I --> False (P)
# B, Gold L --> False (P)
# B, Gold O --> False (P)
# B, Gold U --> False (P)
return 1
cdef class In:
@staticmethod
cdef bint is_valid(const StateC* st, attr_t label) nogil:
cdef int preset_ent_iob = st.B_(0).ent_iob
cdef attr_t preset_ent_label = st.B_(0).ent_type
if label == 0:
return False
elif st.E_(0).ent_type != label:
return False
elif not st.entity_is_open():
return False
elif st.B(1) == -1:
# If we're at the end, we can't I.
return False
elif preset_ent_iob == 3:
return False
elif st.B_(1).ent_iob == 3:
# If we know the next word is B, we can't be I (must be L)
return False
elif preset_ent_iob == 1:
if st.B_(1).ent_iob in (0, 2):
# if next preset is missing or O, this can't be I (must be L)
return False
elif label != preset_ent_label:
# If label isn't right, reject
return False
else:
# Otherwise, force acceptance, even if we're across a sentence
# boundary or the token is whitespace.
return True
elif st.B(1) != -1 and st.B_(1).sent_start == 1:
# Don't allow entities to extend across sentence boundaries
return False
else:
return True
@staticmethod
cdef int transition(StateC* st, attr_t label) nogil:
st.set_ent_tag(st.B(0), 1, label)
st.push()
st.pop()
@staticmethod
cdef weight_t cost(StateClass s, const GoldParseC* gold, attr_t label) nogil:
move = IN
cdef int next_act = gold.ner[s.B(1)].move if s.B(1) >= 0 else OUT
cdef int g_act = gold.ner[s.B(0)].move
cdef attr_t g_tag = gold.ner[s.B(0)].label
cdef bint is_sunk = _entity_is_sunk(s, gold.ner)
if g_act == MISSING:
return 0
elif g_act == BEGIN:
# I, Gold B --> True
# (P of bad open entity sunk, R of this entity sunk)
return 0
elif g_act == IN:
# I, Gold I --> True
# (label forced by prev, if mismatch, P and R both sunk)
return 0
elif g_act == LAST:
# I, Gold L --> True iff this entity sunk and next tag == O
return not (is_sunk and (next_act == OUT or next_act == MISSING))
elif g_act == OUT:
# I, Gold O --> True iff next tag == O
return not (next_act == OUT or next_act == MISSING)
elif g_act == UNIT:
# I, Gold U --> True iff next tag == O
return next_act != OUT
# Support partial supervision in the form of "not this label"
elif g_act == ISNT:
return 0
else:
return 1
cdef class Last:
@staticmethod
cdef bint is_valid(const StateC* st, attr_t label) nogil:
cdef int preset_ent_iob = st.B_(0).ent_iob
cdef attr_t preset_ent_label = st.B_(0).ent_type
if label == 0:
return False
elif not st.entity_is_open():
return False
elif preset_ent_iob == 1 and st.B_(1).ent_iob != 1:
# If a preset entity has I followed by not-I, is L
if label != preset_ent_label:
# If label isn't right, reject
return False
else:
# Otherwise, force acceptance, even if we're across a sentence
# boundary or the token is whitespace.
return True
elif st.E_(0).ent_type != label:
return False
elif st.B_(1).ent_iob == 1:
# If a preset entity has I next, we can't L here.
return False
else:
return True
@staticmethod
cdef int transition(StateC* st, attr_t label) nogil:
st.close_ent()
st.set_ent_tag(st.B(0), 1, label)
st.push()
st.pop()
@staticmethod
cdef weight_t cost(StateClass s, const GoldParseC* gold, attr_t label) nogil:
move = LAST
cdef int g_act = gold.ner[s.B(0)].move
cdef attr_t g_tag = gold.ner[s.B(0)].label
if g_act == MISSING:
return 0
elif g_act == BEGIN:
# L, Gold B --> True
return 0
elif g_act == IN:
# L, Gold I --> True iff this entity sunk
return not _entity_is_sunk(s, gold.ner)
elif g_act == LAST:
# L, Gold L --> True
return 0
elif g_act == OUT:
# L, Gold O --> True
return 0
elif g_act == UNIT:
# L, Gold U --> True
return 0
# Support partial supervision in the form of "not this label"
elif g_act == ISNT:
return 0
else:
return 1
cdef class Unit:
@staticmethod
cdef bint is_valid(const StateC* st, attr_t label) nogil:
cdef int preset_ent_iob = st.B_(0).ent_iob
cdef attr_t preset_ent_label = st.B_(0).ent_type
if label == 0:
# this is only allowed if it's a preset blocked annotation
if preset_ent_label == 0 and preset_ent_iob == 3:
return True
else:
return False
elif st.entity_is_open():
return False
elif st.B_(1).ent_iob == 1:
# If next token is In, we can't be Unit -- must be Begin
return False
elif preset_ent_iob == 3:
# Okay, there's a preset entity here
if label != preset_ent_label:
# Require labels to match
return False
else:
# Otherwise return True, ignoring the whitespace constraint.
return True
elif Lexeme.get_struct_attr(st.B_(0).lex, IS_SPACE):
return False
else:
return True
@staticmethod
cdef int transition(StateC* st, attr_t label) nogil:
st.open_ent(label)
st.close_ent()
st.set_ent_tag(st.B(0), 3, label)
st.push()
st.pop()
@staticmethod
cdef weight_t cost(StateClass s, const GoldParseC* gold, attr_t label) nogil:
cdef int g_act = gold.ner[s.B(0)].move
cdef attr_t g_tag = gold.ner[s.B(0)].label
if g_act == MISSING:
return 0
elif g_act == UNIT:
# U, Gold U --> True iff tag match
return label != g_tag
# Support partial supervision in the form of "not this label"
elif g_act == ISNT:
return label == g_tag
else:
# U, Gold B --> False
# U, Gold I --> False
# U, Gold L --> False
# U, Gold O --> False
return 1
cdef class Out:
@staticmethod
cdef bint is_valid(const StateC* st, attr_t label) nogil:
cdef int preset_ent_iob = st.B_(0).ent_iob
if st.entity_is_open():
return False
elif preset_ent_iob == 3:
return False
elif preset_ent_iob == 1:
return False
else:
return True
@staticmethod
cdef int transition(StateC* st, attr_t label) nogil:
st.set_ent_tag(st.B(0), 2, 0)
st.push()
st.pop()
@staticmethod
cdef weight_t cost(StateClass s, const GoldParseC* gold, attr_t label) nogil:
cdef int g_act = gold.ner[s.B(0)].move
cdef attr_t g_tag = gold.ner[s.B(0)].label
if g_act == ISNT and g_tag == 0:
return 1
elif g_act == MISSING or g_act == ISNT:
return 0
elif g_act == BEGIN:
# O, Gold B --> False
return 1
elif g_act == IN:
# O, Gold I --> True
return 0
elif g_act == LAST:
# O, Gold L --> True
return 0
elif g_act == OUT:
# O, Gold O --> True
return 0
elif g_act == UNIT:
# O, Gold U --> False
return 1
else:
return 1