mirror of
https://github.com/explosion/spaCy.git
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581 lines
20 KiB
Cython
581 lines
20 KiB
Cython
# cython: profile=True
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# cython: cdivision=True
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# cython: infer_types=True
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# coding: utf-8
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from __future__ import unicode_literals
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from cpython.ref cimport Py_INCREF
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from cymem.cymem cimport Pool
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from collections import OrderedDict
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from thinc.extra.search cimport Beam
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from .stateclass cimport StateClass
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from ._state cimport StateC
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from .nonproj import is_nonproj_tree
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from .transition_system cimport move_cost_func_t, label_cost_func_t
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from ..gold cimport GoldParse, GoldParseC
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from ..structs cimport TokenC
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DEF NON_MONOTONIC = True
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DEF USE_BREAK = True
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cdef weight_t MIN_SCORE = -90000
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# Break transition from here
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# http://www.aclweb.org/anthology/P13-1074
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cdef enum:
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SHIFT
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REDUCE
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LEFT
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RIGHT
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BREAK
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N_MOVES
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MOVE_NAMES = [None] * N_MOVES
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MOVE_NAMES[SHIFT] = 'S'
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MOVE_NAMES[REDUCE] = 'D'
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MOVE_NAMES[LEFT] = 'L'
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MOVE_NAMES[RIGHT] = 'R'
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MOVE_NAMES[BREAK] = 'B'
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# Helper functions for the arc-eager oracle
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cdef weight_t push_cost(StateClass stcls, const GoldParseC* gold, int target) nogil:
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cdef weight_t cost = 0
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cdef int i, S_i
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for i in range(stcls.stack_depth()):
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S_i = stcls.S(i)
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if gold.heads[target] == S_i:
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cost += 1
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if gold.heads[S_i] == target and (NON_MONOTONIC or not stcls.has_head(S_i)):
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cost += 1
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cost += Break.is_valid(stcls.c, 0) and Break.move_cost(stcls, gold) == 0
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return cost
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cdef weight_t pop_cost(StateClass stcls, const GoldParseC* gold, int target) nogil:
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cdef weight_t cost = 0
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cdef int i, B_i
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for i in range(stcls.buffer_length()):
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B_i = stcls.B(i)
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cost += gold.heads[B_i] == target
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cost += gold.heads[target] == B_i
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if gold.heads[B_i] == B_i or gold.heads[B_i] < target:
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break
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if Break.is_valid(stcls.c, 0) and Break.move_cost(stcls, gold) == 0:
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cost += 1
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return cost
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cdef weight_t arc_cost(StateClass stcls, const GoldParseC* gold, int head, int child) nogil:
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if arc_is_gold(gold, head, child):
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return 0
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elif stcls.H(child) == gold.heads[child]:
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return 1
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# Head in buffer
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elif gold.heads[child] >= stcls.B(0) and stcls.B(1) != 0:
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return 1
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else:
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return 0
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cdef bint arc_is_gold(const GoldParseC* gold, int head, int child) nogil:
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if not gold.has_dep[child]:
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return True
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elif gold.heads[child] == head:
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return True
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else:
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return False
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cdef bint label_is_gold(const GoldParseC* gold, int head, int child, attr_t label) nogil:
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if not gold.has_dep[child]:
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return True
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elif label == 0:
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return True
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elif gold.labels[child] == label:
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return True
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else:
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return False
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cdef bint _is_gold_root(const GoldParseC* gold, int word) nogil:
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return gold.heads[word] == word or not gold.has_dep[word]
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cdef class Shift:
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@staticmethod
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cdef bint is_valid(const StateC* st, attr_t label) nogil:
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sent_start = st._sent[st.B_(0).l_edge].sent_start
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return st.buffer_length() >= 2 and not st.shifted[st.B(0)] and sent_start != 1
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@staticmethod
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cdef int transition(StateC* st, attr_t label) nogil:
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st.push()
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st.fast_forward()
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@staticmethod
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cdef weight_t cost(StateClass st, const GoldParseC* gold, attr_t label) nogil:
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return Shift.move_cost(st, gold) + Shift.label_cost(st, gold, label)
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@staticmethod
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cdef inline weight_t move_cost(StateClass s, const GoldParseC* gold) nogil:
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return push_cost(s, gold, s.B(0))
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@staticmethod
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cdef inline weight_t label_cost(StateClass s, const GoldParseC* gold, attr_t label) nogil:
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return 0
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cdef class Reduce:
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@staticmethod
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cdef bint is_valid(const StateC* st, attr_t label) nogil:
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return st.stack_depth() >= 2
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@staticmethod
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cdef int transition(StateC* st, attr_t label) nogil:
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if st.has_head(st.S(0)):
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st.pop()
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else:
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st.unshift()
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st.fast_forward()
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@staticmethod
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cdef weight_t cost(StateClass s, const GoldParseC* gold, attr_t label) nogil:
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return Reduce.move_cost(s, gold) + Reduce.label_cost(s, gold, label)
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@staticmethod
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cdef inline weight_t move_cost(StateClass st, const GoldParseC* gold) nogil:
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cost = pop_cost(st, gold, st.S(0))
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if not st.has_head(st.S(0)):
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# Decrement cost for the arcs e save
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for i in range(1, st.stack_depth()):
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S_i = st.S(i)
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if gold.heads[st.S(0)] == S_i:
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cost -= 1
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if gold.heads[S_i] == st.S(0):
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cost -= 1
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if Break.is_valid(st.c, 0) and Break.move_cost(st, gold) == 0:
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cost -= 1
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return cost
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@staticmethod
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cdef inline weight_t label_cost(StateClass s, const GoldParseC* gold, attr_t label) nogil:
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return 0
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cdef class LeftArc:
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@staticmethod
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cdef bint is_valid(const StateC* st, attr_t label) nogil:
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sent_start = st._sent[st.B_(0).l_edge].sent_start
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return sent_start != 1
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@staticmethod
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cdef int transition(StateC* st, attr_t label) nogil:
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st.add_arc(st.B(0), st.S(0), label)
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st.pop()
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st.fast_forward()
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@staticmethod
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cdef weight_t cost(StateClass s, const GoldParseC* gold, attr_t label) nogil:
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return LeftArc.move_cost(s, gold) + LeftArc.label_cost(s, gold, label)
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@staticmethod
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cdef inline weight_t move_cost(StateClass s, const GoldParseC* gold) nogil:
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cdef weight_t cost = 0
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if arc_is_gold(gold, s.B(0), s.S(0)):
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# Have a negative cost if we 'recover' from the wrong dependency
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return 0 if not s.has_head(s.S(0)) else -1
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else:
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# Account for deps we might lose between S0 and stack
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if not s.has_head(s.S(0)):
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for i in range(1, s.stack_depth()):
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cost += gold.heads[s.S(i)] == s.S(0)
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cost += gold.heads[s.S(0)] == s.S(i)
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return cost + pop_cost(s, gold, s.S(0)) + arc_cost(s, gold, s.B(0), s.S(0))
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@staticmethod
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cdef inline weight_t label_cost(StateClass s, const GoldParseC* gold, attr_t label) nogil:
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return arc_is_gold(gold, s.B(0), s.S(0)) and not label_is_gold(gold, s.B(0), s.S(0), label)
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cdef class RightArc:
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@staticmethod
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cdef bint is_valid(const StateC* st, attr_t label) nogil:
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# If there's (perhaps partial) parse pre-set, don't allow cycle.
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sent_start = st._sent[st.B_(0).l_edge].sent_start
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return sent_start != 1 and st.H(st.S(0)) != st.B(0)
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@staticmethod
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cdef int transition(StateC* st, attr_t label) nogil:
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st.add_arc(st.S(0), st.B(0), label)
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st.push()
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st.fast_forward()
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@staticmethod
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cdef inline weight_t cost(StateClass s, const GoldParseC* gold, attr_t label) nogil:
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return RightArc.move_cost(s, gold) + RightArc.label_cost(s, gold, label)
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@staticmethod
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cdef inline weight_t move_cost(StateClass s, const GoldParseC* gold) nogil:
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if arc_is_gold(gold, s.S(0), s.B(0)):
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return 0
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elif s.c.shifted[s.B(0)]:
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return push_cost(s, gold, s.B(0))
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else:
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return push_cost(s, gold, s.B(0)) + arc_cost(s, gold, s.S(0), s.B(0))
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@staticmethod
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cdef weight_t label_cost(StateClass s, const GoldParseC* gold, attr_t label) nogil:
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return arc_is_gold(gold, s.S(0), s.B(0)) and not label_is_gold(gold, s.S(0), s.B(0), label)
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cdef class Break:
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@staticmethod
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cdef bint is_valid(const StateC* st, attr_t label) nogil:
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cdef int i
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if not USE_BREAK:
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return False
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elif st.at_break():
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return False
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elif st.stack_depth() < 1:
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return False
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elif st.B_(0).l_edge < 0:
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return False
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elif st._sent[st.B_(0).l_edge].sent_start < 0:
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return False
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else:
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return True
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@staticmethod
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cdef int transition(StateC* st, attr_t label) nogil:
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st.set_break(st.B_(0).l_edge)
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st.fast_forward()
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@staticmethod
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cdef weight_t cost(StateClass s, const GoldParseC* gold, attr_t label) nogil:
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return Break.move_cost(s, gold) + Break.label_cost(s, gold, label)
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@staticmethod
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cdef inline weight_t move_cost(StateClass s, const GoldParseC* gold) nogil:
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cdef weight_t cost = 0
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cdef int i, j, S_i, B_i
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for i in range(s.stack_depth()):
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S_i = s.S(i)
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for j in range(s.buffer_length()):
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B_i = s.B(j)
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cost += gold.heads[S_i] == B_i
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cost += gold.heads[B_i] == S_i
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if cost != 0:
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return cost
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# Check for sentence boundary --- if it's here, we can't have any deps
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# between stack and buffer, so rest of action is irrelevant.
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s0_root = _get_root(s.S(0), gold)
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b0_root = _get_root(s.B(0), gold)
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if s0_root != b0_root or s0_root == -1 or b0_root == -1:
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return cost
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else:
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return cost + 1
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@staticmethod
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cdef inline weight_t label_cost(StateClass s, const GoldParseC* gold, attr_t label) nogil:
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return 0
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cdef int _get_root(int word, const GoldParseC* gold) nogil:
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while gold.heads[word] != word and gold.has_dep[word] and word >= 0:
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word = gold.heads[word]
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if not gold.has_dep[word]:
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return -1
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else:
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return word
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cdef void* _init_state(Pool mem, int length, void* tokens) except NULL:
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st = new StateC(<const TokenC*>tokens, length)
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for i in range(st.length):
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if st._sent[i].dep == 0:
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st._sent[i].l_edge = i
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st._sent[i].r_edge = i
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st._sent[i].head = 0
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st._sent[i].dep = 0
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st._sent[i].l_kids = 0
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st._sent[i].r_kids = 0
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st.fast_forward()
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return <void*>st
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cdef class ArcEager(TransitionSystem):
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def __init__(self, *args, **kwargs):
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TransitionSystem.__init__(self, *args, **kwargs)
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self.init_beam_state = _init_state
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@classmethod
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def get_actions(cls, **kwargs):
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actions = kwargs.get('actions', OrderedDict((
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(SHIFT, ['']),
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(REDUCE, ['']),
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(RIGHT, []),
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(LEFT, ['subtok']),
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(BREAK, ['ROOT']))
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))
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seen_actions = set()
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for label in kwargs.get('left_labels', []):
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if label.upper() != 'ROOT':
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if (LEFT, label) not in seen_actions:
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actions[LEFT].append(label)
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seen_actions.add((LEFT, label))
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for label in kwargs.get('right_labels', []):
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if label.upper() != 'ROOT':
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if (RIGHT, label) not in seen_actions:
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actions[RIGHT].append(label)
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seen_actions.add((RIGHT, label))
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for raw_text, sents in kwargs.get('gold_parses', []):
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for (ids, words, tags, heads, labels, iob), ctnts in sents:
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for child, head, label in zip(ids, heads, labels):
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if label.upper() == 'ROOT':
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label = 'ROOT'
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if label != 'ROOT':
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if head < child:
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if (RIGHT, label) not in seen_actions:
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actions[RIGHT].append(label)
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seen_actions.add((RIGHT, label))
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elif head > child:
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if (LEFT, label) not in seen_actions:
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actions[LEFT].append(label)
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seen_actions.add((LEFT, label))
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return actions
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property action_types:
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def __get__(self):
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return (SHIFT, REDUCE, LEFT, RIGHT, BREAK)
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def is_gold_parse(self, StateClass state, GoldParse gold):
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predicted = set()
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truth = set()
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for i in range(gold.length):
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if gold.cand_to_gold[i] is None:
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continue
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if state.safe_get(i).dep:
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predicted.add((i, state.H(i),
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self.strings[state.safe_get(i).dep]))
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else:
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predicted.add((i, state.H(i), 'ROOT'))
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id_, word, tag, head, dep, ner = gold.orig_annot[gold.cand_to_gold[i]]
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truth.add((id_, head, dep))
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return truth == predicted
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def has_gold(self, GoldParse gold, start=0, end=None):
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end = end or len(gold.heads)
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if all([tag is None for tag in gold.heads[start:end]]):
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return False
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else:
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return True
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def preprocess_gold(self, GoldParse gold):
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if not self.has_gold(gold):
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return None
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for i in range(gold.length):
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# Missing values
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if gold.heads[i] is None or gold.labels[i] is None:
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gold.c.heads[i] = i
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gold.c.has_dep[i] = False
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else:
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label = gold.labels[i]
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gold.c.has_dep[i] = True
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if label.upper() == 'ROOT':
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label = 'ROOT'
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gold.c.heads[i] = gold.heads[i]
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gold.c.labels[i] = self.strings.add(label)
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return gold
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def get_beam_parses(self, Beam beam):
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parses = []
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probs = beam.probs
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for i in range(beam.size):
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state = <StateC*>beam.at(i)
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if state.is_final():
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self.finalize_state(state)
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prob = probs[i]
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parse = []
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for j in range(state.length):
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head = state.H(j)
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label = self.strings[state._sent[j].dep]
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parse.append((head, j, label))
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parses.append((prob, parse))
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return parses
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cdef Transition lookup_transition(self, object name) except *:
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if '-' in name:
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move_str, label_str = name.split('-', 1)
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label = self.strings[label_str]
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else:
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move_str = name
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label = 0
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move = MOVE_NAMES.index(move_str)
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for i in range(self.n_moves):
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if self.c[i].move == move and self.c[i].label == label:
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return self.c[i]
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return Transition(clas=0, move=MISSING, label=0)
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def move_name(self, int move, attr_t label):
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label_str = self.strings[label]
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if label_str:
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return MOVE_NAMES[move] + '-' + label_str
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else:
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return MOVE_NAMES[move]
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cdef Transition init_transition(self, int clas, int move, attr_t label) except *:
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# TODO: Apparent Cython bug here when we try to use the Transition()
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# constructor with the function pointers
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cdef Transition t
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t.score = 0
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t.clas = clas
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t.move = move
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t.label = label
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if move == SHIFT:
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t.is_valid = Shift.is_valid
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t.do = Shift.transition
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t.get_cost = Shift.cost
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elif move == REDUCE:
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t.is_valid = Reduce.is_valid
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t.do = Reduce.transition
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t.get_cost = Reduce.cost
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elif move == LEFT:
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t.is_valid = LeftArc.is_valid
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t.do = LeftArc.transition
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t.get_cost = LeftArc.cost
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elif move == RIGHT:
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t.is_valid = RightArc.is_valid
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t.do = RightArc.transition
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t.get_cost = RightArc.cost
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elif move == BREAK:
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t.is_valid = Break.is_valid
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t.do = Break.transition
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t.get_cost = Break.cost
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else:
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raise Exception(move)
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return t
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cdef int initialize_state(self, StateC* st) nogil:
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for i in range(st.length):
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if st._sent[i].dep == 0:
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st._sent[i].l_edge = i
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st._sent[i].r_edge = i
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st._sent[i].head = 0
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st._sent[i].dep = 0
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st._sent[i].l_kids = 0
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st._sent[i].r_kids = 0
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st.fast_forward()
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cdef int finalize_state(self, StateC* st) nogil:
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cdef int i
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for i in range(st.length):
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if st._sent[i].head == 0:
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st._sent[i].dep = self.root_label
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def finalize_doc(self, doc):
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doc.is_parsed = True
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cdef int set_valid(self, int* output, const StateC* st) nogil:
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cdef bint[N_MOVES] is_valid
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is_valid[SHIFT] = Shift.is_valid(st, 0)
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is_valid[REDUCE] = Reduce.is_valid(st, 0)
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is_valid[LEFT] = LeftArc.is_valid(st, 0)
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is_valid[RIGHT] = RightArc.is_valid(st, 0)
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is_valid[BREAK] = Break.is_valid(st, 0)
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cdef int i
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for i in range(self.n_moves):
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output[i] = is_valid[self.c[i].move]
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|
|
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cdef int set_costs(self, int* is_valid, weight_t* costs,
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StateClass stcls, GoldParse gold) except -1:
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cdef int i, move
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cdef attr_t label
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cdef label_cost_func_t[N_MOVES] label_cost_funcs
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cdef move_cost_func_t[N_MOVES] move_cost_funcs
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cdef weight_t[N_MOVES] move_costs
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for i in range(N_MOVES):
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move_costs[i] = 9000
|
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move_cost_funcs[SHIFT] = Shift.move_cost
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move_cost_funcs[REDUCE] = Reduce.move_cost
|
|
move_cost_funcs[LEFT] = LeftArc.move_cost
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|
move_cost_funcs[RIGHT] = RightArc.move_cost
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move_cost_funcs[BREAK] = Break.move_cost
|
|
|
|
label_cost_funcs[SHIFT] = Shift.label_cost
|
|
label_cost_funcs[REDUCE] = Reduce.label_cost
|
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label_cost_funcs[LEFT] = LeftArc.label_cost
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|
label_cost_funcs[RIGHT] = RightArc.label_cost
|
|
label_cost_funcs[BREAK] = Break.label_cost
|
|
|
|
cdef attr_t* labels = gold.c.labels
|
|
cdef int* heads = gold.c.heads
|
|
|
|
n_gold = 0
|
|
for i in range(self.n_moves):
|
|
if self.c[i].is_valid(stcls.c, self.c[i].label):
|
|
is_valid[i] = True
|
|
move = self.c[i].move
|
|
label = self.c[i].label
|
|
if move_costs[move] == 9000:
|
|
move_costs[move] = move_cost_funcs[move](stcls, &gold.c)
|
|
costs[i] = move_costs[move] + label_cost_funcs[move](stcls, &gold.c, label)
|
|
n_gold += costs[i] <= 0
|
|
else:
|
|
is_valid[i] = False
|
|
costs[i] = 9000
|
|
if n_gold < 1:
|
|
# Check label set --- leading cause
|
|
label_set = set([self.strings[self.c[i].label] for i in range(self.n_moves)])
|
|
for label_str in gold.labels:
|
|
if label_str is not None and label_str not in label_set:
|
|
raise ValueError("Cannot get gold parser action: unknown label: %s" % label_str)
|
|
# Check projectivity --- other leading cause
|
|
if is_nonproj_tree(gold.heads):
|
|
raise ValueError(
|
|
"Could not find a gold-standard action to supervise the "
|
|
"dependency parser. Likely cause: the tree is "
|
|
"non-projective (i.e. it has crossing arcs -- see "
|
|
"spacy/syntax/nonproj.pyx for definitions). The ArcEager "
|
|
"transition system only supports projective trees. To "
|
|
"learn non-projective representations, transform the data "
|
|
"before training and after parsing. Either pass "
|
|
"make_projective=True to the GoldParse class, or use "
|
|
"spacy.syntax.nonproj.preprocess_training_data.")
|
|
else:
|
|
print(gold.orig_annot)
|
|
print(gold.words)
|
|
print(gold.heads)
|
|
print(gold.labels)
|
|
print(gold.sent_starts)
|
|
raise ValueError(
|
|
"Could not find a gold-standard action to supervise the"
|
|
"dependency parser. The GoldParse was projective. The "
|
|
"transition system has %d actions. State at failure: %s"
|
|
% (self.n_moves, stcls.print_state(gold.words)))
|
|
assert n_gold >= 1
|
|
|
|
def get_beam_annot(self, Beam beam):
|
|
length = (<StateC*>beam.at(0)).length
|
|
heads = [{} for _ in range(length)]
|
|
deps = [{} for _ in range(length)]
|
|
probs = beam.probs
|
|
for i in range(beam.size):
|
|
state = <StateC*>beam.at(i)
|
|
self.finalize_state(state)
|
|
if state.is_final():
|
|
prob = probs[i]
|
|
for j in range(state.length):
|
|
head = j + state._sent[j].head
|
|
dep = state._sent[j].dep
|
|
heads[j].setdefault(head, 0.0)
|
|
heads[j][head] += prob
|
|
deps[j].setdefault(dep, 0.0)
|
|
deps[j][dep] += prob
|
|
return heads, deps
|