spaCy/spacy/tokens.pyx
2014-11-03 00:23:20 +11:00

130 lines
4.2 KiB
Cython

# cython: profile=True
from .lexeme cimport *
cimport cython
DEF PADDING = 5
cdef int bounds_check(int i, int length, int padding) except -1:
if (i + padding) < 0:
raise IndexError
if (i - padding) >= length:
raise IndexError
cdef class Tokens:
"""A sequence of references to Lexeme objects.
The Tokens class provides fast and memory-efficient access to lexical features,
and can efficiently export the data to a numpy array. Specific languages
create their own Tokens subclasses, to provide more convenient access to
language-specific features.
>>> from spacy.en import EN
>>> tokens = EN.tokenize('An example sentence.')
>>> tokens.string(0)
'An'
>>> tokens.prob(0) > tokens.prob(1)
True
>>> tokens.can_noun(0)
False
>>> tokens.can_noun(1)
True
"""
def __init__(self, StringStore string_store, string_length=0):
self._string_store = string_store
if string_length >= 3:
size = int(string_length / 3.0)
else:
size = 5
self.mem = Pool()
# Guarantee self.lex[i-x], for any i >= 0 and x < padding is in bounds
# However, we need to remember the true starting places, so that we can
# realloc.
self._lex_ptr = <Lexeme**>self.mem.alloc(size + (PADDING*2), sizeof(Lexeme*))
self._idx_ptr = <int*>self.mem.alloc(size + (PADDING*2), sizeof(int))
self._pos_ptr = <int*>self.mem.alloc(size + (PADDING*2), sizeof(int))
self.lex = self._lex_ptr
self.idx = self._idx_ptr
self.pos = self._pos_ptr
cdef int i
for i in range(size + (PADDING*2)):
self.lex[i] = &EMPTY_LEXEME
self.lex += PADDING
self.idx += PADDING
self.pos += PADDING
self.max_length = size
self.length = 0
def __getitem__(self, i):
bounds_check(i, self.length, PADDING)
return Token(self._string_store, i, self.idx[i], self.pos[i], self.lex[i][0])
def __len__(self):
return self.length
cdef int push_back(self, int idx, Lexeme* lexeme) except -1:
if self.length == self.max_length:
self._realloc(self.length * 2)
self.lex[self.length] = lexeme
self.idx[self.length] = idx
self.pos[self.length] = 0
self.length += 1
return idx + lexeme.length
cdef int extend(self, int idx, Lexeme** lexemes, int n) except -1:
cdef int i
if lexemes == NULL:
return idx
elif n == 0:
i = 0
while lexemes[i] != NULL:
idx = self.push_back(idx, lexemes[i])
i += 1
else:
for i in range(n):
idx = self.push_back(idx, lexemes[i])
return idx
def _realloc(self, new_size):
self.max_length = new_size
n = new_size + (PADDING * 2)
self._lex_ptr = <Lexeme**>self.mem.realloc(self._lex_ptr, n * sizeof(Lexeme*))
self._idx_ptr = <int*>self.mem.realloc(self._idx_ptr, n * sizeof(int))
self._pos_ptr = <int*>self.mem.realloc(self._pos_ptr, n * sizeof(int))
self.lex = self._lex_ptr + PADDING
self.idx = self._idx_ptr + PADDING
self.pos = self._pos_ptr + PADDING
for i in range(self.length, self.max_length + PADDING):
self.lex[i] = &EMPTY_LEXEME
@cython.freelist(64)
cdef class Token:
def __init__(self, StringStore string_store, int i, int idx, int pos, dict lex):
self._string_store = string_store
self.idx = idx
self.pos = pos
self.i = i
self.id = lex['id']
self.cluster = lex['cluster']
self.length = lex['length']
self.postype = lex['postype']
self.sensetype = lex['supersense']
self.sic = lex['sic']
self.norm = lex['norm']
self.shape = lex['shape']
self.suffix = lex['asciied']
self.prefix = lex['prefix']
self.prob = lex['prob']
self.flags = lex['flags']
property string:
def __get__(self):
if self.sic == 0:
return ''
cdef bytes utf8string = self._string_store[self.sic]
return utf8string.decode('utf8')