spaCy/spacy/index.pyx
2014-12-20 01:43:26 +11:00

121 lines
4.1 KiB
Cython

"""Create a term-document matrix"""
cimport cython
from libc.stdint cimport int64_t
from libc.string cimport memmove
from cymem.cymem cimport Address
from .lexeme cimport Lexeme, get_attr
from .tokens cimport TokenC
from .typedefs cimport hash_t
from preshed.maps cimport MapStruct, Cell, map_get, map_set, map_init
from murmurhash.mrmr cimport hash64
cdef class Index:
def __init__(self, attr_id_t attr_id):
self.attr_id = attr_id
self.max_value = 0
cpdef int count(self, Tokens tokens) except -1:
cdef PreshCounter counts = PreshCounter(2 ** 8)
cdef attr_id_t attr_id = self.attr_id
cdef attr_t term
cdef int i
for i in range(tokens.length):
term = get_attr(tokens.data[i].lex, attr_id)
counts.inc(term, 1)
if term > self.max_value:
self.max_value = term
cdef count_t count
cdef count_vector_t doc_counts
for term, count in counts:
doc_counts.push_back(pair[id_t, count_t](term, count))
self.counts.push_back(doc_counts)
cdef class DecisionMemory:
def __init__(self, class_names):
self.class_names = class_names
self.n_classes = len(class_names)
self.mem = Pool()
self._counts = PreshCounter()
self._class_counts = PreshCounter()
self.memos = PreshMap()
def load(self, loc, thresh=50):
cdef:
count_t freq
hash_t key
int clas
for line in open(loc):
freq, key, clas = [int(p) for p in line.split()]
if thresh == 0 or freq >= thresh:
self.memos.set(key, <void*>(clas+1))
def __getitem__(self, ids):
cdef id_t[2] context
context[0] = context[0]
context[1] = context[1]
cdef hash_t context_key = hash64(context, 2 * sizeof(id_t), 0)
cdef hash_t[2] class_context
class_context[0] = context_key
counts = {}
cdef id_t i
for i, clas in enumerate(self.clas_names):
class_context[1] = <hash_t>i
key = hash64(class_context, sizeof(hash_t) * 2, 0)
count = self._class_counts[key]
counts[clas] = count
return counts
@cython.cdivision(True)
def iter_contexts(self, float min_acc=0.99, count_t min_freq=10):
cdef Address counts_addr = Address(self.n_classes, sizeof(count_t))
cdef count_t* counts = <count_t*>counts_addr.ptr
cdef MapStruct* context_counts = self._counts.c_map
cdef hash_t context_key
cdef count_t context_freq
cdef int best_class
cdef float acc
cdef int i
for i in range(context_counts.length):
context_key = context_counts.cells[i].key
context_freq = <count_t>context_counts.cells[i].value
if context_key != 0 and context_freq >= min_freq:
best_class = self.find_best_class(counts, context_key)
acc = counts[best_class] / context_freq
if acc >= min_acc:
yield counts[best_class], context_key, best_class
cdef int inc(self, hash_t context_key, hash_t clas, count_t inc) except -1:
cdef hash_t context_and_class_key
cdef hash_t[2] context_and_class
context_and_class[0] = context_key
context_and_class[1] = clas
context_and_class_key = hash64(context_and_class, 2 * sizeof(hash_t), 0)
self._counts.inc(context_key, inc)
self._class_counts.inc(context_and_class_key, inc)
cdef int find_best_class(self, count_t* counts, hash_t context_key) except -1:
cdef hash_t[2] unhashed_key
unhashed_key[0] = context_key
cdef count_t total = 0
cdef hash_t key
cdef int clas
cdef int best
cdef int mode = 0
for clas in range(self.n_classes):
unhashed_key[1] = <hash_t>clas
key = hash64(unhashed_key, sizeof(hash_t) * 2, 0)
count = self._class_counts[key]
counts[clas] = count
if count >= mode:
mode = count
best = clas
total += count
return best