spaCy/spacy/spacy.pyx
2014-07-07 05:10:46 +02:00

106 lines
3.6 KiB
Cython

from __future__ import unicode_literals
from ext.murmurhash cimport MurmurHash64A
from ext.murmurhash cimport MurmurHash64B
from spacy.lexeme cimport init_lexeme
from spacy.lexeme cimport BLANK_WORD
from spacy.string_tools cimport is_whitespace
from . import util
cdef load_tokenization(Vocab& vocab, dict bacov, token_rules):
cdef Lexeme* word
cdef StringHash hashed
for chunk, lex, tokens in token_rules:
hashed = hash_string(chunk, len(chunk))
assert vocab[hashed] == 0, chunk
word = _add(vocab, bacov, <Splitter>NULL, hashed, lex, len(lex), len(lex))
for i, lex in enumerate(tokens):
token_string = '%s:@:%d:@:%s' % (chunk, i, lex)
length = len(token_string)
hashed = hash_string(token_string, length)
word.tail = _add(vocab, bacov, <Splitter>NULL, hashed, lex, 0, len(lex))
word = word.tail
cdef vector[Lexeme_addr] tokenize(Vocab& vocab, dict bacov, Splitter splitter,
unicode string) except *:
cdef size_t length = len(string)
cdef Py_UNICODE* characters = <Py_UNICODE*>string
cdef size_t i
cdef Py_UNICODE c
cdef vector[Lexeme_addr] tokens = vector[Lexeme_addr]()
cdef unicode current = u''
cdef Lexeme* token
for i in range(length):
c = characters[i]
if is_whitespace(c):
if current:
token = <Lexeme*>lookup(vocab, bacov, splitter, -1, current)
while token != NULL:
tokens.push_back(<Lexeme_addr>token)
token = token.tail
current = u''
else:
current += c
if current:
token = <Lexeme*>lookup(vocab, bacov, splitter, -1, current)
while token != NULL:
tokens.push_back(<Lexeme_addr>token)
token = token.tail
return tokens
cdef Lexeme_addr lookup(Vocab& vocab, dict bacov, Splitter find_split, int start,
unicode string) except 0:
'''Fetch a Lexeme representing a word string. If the word has not been seen,
construct one, splitting off any attached punctuation or clitics. A
reference to BLANK_WORD is returned for the empty string.
To specify the boundaries of the word if it has not been seen, use lookup_chunk.
'''
if string == '':
return <Lexeme_addr>&BLANK_WORD
cdef size_t length = len(string)
cdef StringHash hashed = hash_string(string, length)
cdef Lexeme* word_ptr = <Lexeme*>vocab[hashed]
if word_ptr == NULL:
start = find_split(string, length) if start == -1 else start
word_ptr = _add(vocab, bacov, find_split, hashed, string, start, length)
return <Lexeme_addr>word_ptr
cpdef vector[size_t] expand_chunk(size_t addr) except *:
cdef vector[size_t] tokens = vector[size_t]()
word = <Lexeme*>addr
while word is not NULL:
tokens.push_back(<size_t>word)
word = word.tail
return tokens
cdef StringHash hash_string(unicode s, size_t length) except 0:
'''Hash unicode with MurmurHash64A'''
assert length
return MurmurHash64A(<Py_UNICODE*>s, length * sizeof(Py_UNICODE), 0)
cdef unicode unhash(dict bacov, StringHash hash_value):
'''Fetch a string from the reverse index, given its hash value.'''
return bacov[hash_value]
cdef Lexeme* _add(Vocab& vocab, dict bacov, Splitter find_split, StringHash hashed,
unicode string, int split, size_t length) except NULL:
assert string
assert split <= length
word = init_lexeme(vocab, bacov, find_split, string, hashed, split, length)
vocab[hashed] = <Lexeme_addr>word
bacov[hashed] = string
return word