spaCy/spacy/strings.pyx
2015-07-16 17:35:53 +02:00

96 lines
3.3 KiB
Cython

import codecs
from libc.string cimport memcpy
from murmurhash.mrmr cimport hash64
from .typedefs cimport hash_t
SEPARATOR = '\n|-SEP-|\n'
cpdef hash_t hash_string(unicode string) except 0:
chars = <Py_UNICODE*>string
return hash64(chars, len(string) * sizeof(Py_UNICODE), 0)
cdef class StringStore:
'''Map strings to and from integer IDs.'''
def __init__(self):
self.mem = Pool()
self._map = PreshMap()
self._resize_at = 10000
self.strings = <Utf8Str*>self.mem.alloc(self._resize_at, sizeof(Utf8Str))
self.size = 1
property size:
def __get__(self):
return self.size-1
def __len__(self):
return self.size
def __getitem__(self, object string_or_id):
cdef bytes byte_string
cdef const Utf8Str* utf8str
if isinstance(string_or_id, int) or isinstance(string_or_id, long):
if string_or_id == 0:
return u''
elif string_or_id < 1 or string_or_id >= self.size:
raise IndexError(string_or_id)
utf8str = &self.strings[<int>string_or_id]
return utf8str.chars[:utf8str.length].decode('utf8')
elif isinstance(string_or_id, bytes):
utf8str = self.intern(<char*>string_or_id, len(string_or_id))
return utf8str.i
elif isinstance(string_or_id, unicode):
byte_string = string_or_id.encode('utf8')
utf8str = self.intern(<char*>byte_string, len(byte_string))
return utf8str.i
else:
raise TypeError(type(string_or_id))
cdef const Utf8Str* intern(self, char* chars, int length) except NULL:
# 0 means missing, but we don't bother offsetting the index. We waste
# slot 0 to simplify the code, because it doesn't matter.
assert length != 0
cdef hash_t key = hash64(chars, length * sizeof(char), 0)
cdef void* value = self._map.get(key)
cdef size_t i
if value == NULL:
if self.size == self._resize_at:
self._resize_at *= 2
self.strings = <Utf8Str*>self.mem.realloc(self.strings, self._resize_at * sizeof(Utf8Str))
i = self.size
self.strings[i].i = self.size
self.strings[i].key = key
self.strings[i].chars = <unsigned char*>self.mem.alloc(length, sizeof(char))
memcpy(self.strings[i].chars, chars, length)
self.strings[i].length = length
self._map.set(key, <void*>self.size)
self.size += 1
else:
i = <size_t>value
return &self.strings[i]
def dump(self, loc):
cdef Utf8Str* string
cdef bytes py_string
cdef int i
with codecs.open(loc, 'w', 'utf8') as file_:
for i in range(self.size):
string = &self.strings[i]
py_string = string.chars[:string.length]
file_.write(py_string.decode('utf8'))
file_.write(SEPARATOR)
def load(self, loc):
with codecs.open(loc, 'r', 'utf8') as file_:
strings = file_.read().split(SEPARATOR)
cdef unicode string
cdef bytes byte_string
for string in strings[1:]:
byte_string = string.encode('utf8')
self.intern(byte_string, len(byte_string))