aoc-2022/venv/Lib/site-packages/pandas/_libs/hashtable.pyx

184 lines
4.5 KiB
Cython

cimport cython
from cpython.mem cimport (
PyMem_Free,
PyMem_Malloc,
)
from cpython.ref cimport (
Py_INCREF,
PyObject,
)
from libc.stdlib cimport (
free,
malloc,
)
import numpy as np
cimport numpy as cnp
from numpy cimport (
float64_t,
ndarray,
uint8_t,
uint32_t,
)
from numpy.math cimport NAN
cnp.import_array()
from pandas._libs cimport util
from pandas._libs.dtypes cimport numeric_object_t
from pandas._libs.khash cimport (
KHASH_TRACE_DOMAIN,
are_equivalent_float32_t,
are_equivalent_float64_t,
are_equivalent_khcomplex64_t,
are_equivalent_khcomplex128_t,
kh_needed_n_buckets,
kh_python_hash_equal,
kh_python_hash_func,
kh_str_t,
khcomplex64_t,
khcomplex128_t,
khiter_t,
)
from pandas._libs.missing cimport checknull
def get_hashtable_trace_domain():
return KHASH_TRACE_DOMAIN
def object_hash(obj):
return kh_python_hash_func(obj)
def objects_are_equal(a, b):
return kh_python_hash_equal(a, b)
cdef int64_t NPY_NAT = util.get_nat()
SIZE_HINT_LIMIT = (1 << 20) + 7
cdef Py_ssize_t _INIT_VEC_CAP = 128
include "hashtable_class_helper.pxi"
include "hashtable_func_helper.pxi"
# map derived hash-map types onto basic hash-map types:
if np.dtype(np.intp) == np.dtype(np.int64):
IntpHashTable = Int64HashTable
unique_label_indices = _unique_label_indices_int64
elif np.dtype(np.intp) == np.dtype(np.int32):
IntpHashTable = Int32HashTable
unique_label_indices = _unique_label_indices_int32
else:
raise ValueError(np.dtype(np.intp))
cdef class Factorizer:
cdef readonly:
Py_ssize_t count
def __cinit__(self, size_hint: int):
self.count = 0
def get_count(self) -> int:
return self.count
cdef class ObjectFactorizer(Factorizer):
cdef public:
PyObjectHashTable table
ObjectVector uniques
def __cinit__(self, size_hint: int):
self.table = PyObjectHashTable(size_hint)
self.uniques = ObjectVector()
def factorize(
self, ndarray[object] values, sort=False, na_sentinel=-1, na_value=None
) -> np.ndarray:
"""
Returns
-------
np.ndarray[np.intp]
Examples
--------
Factorize values with nans replaced by na_sentinel
>>> fac = ObjectFactorizer(3)
>>> fac.factorize(np.array([1,2,np.nan], dtype='O'), na_sentinel=20)
array([ 0, 1, 20])
"""
cdef:
ndarray[intp_t] labels
if self.uniques.external_view_exists:
uniques = ObjectVector()
uniques.extend(self.uniques.to_array())
self.uniques = uniques
labels = self.table.get_labels(values, self.uniques,
self.count, na_sentinel, na_value)
mask = (labels == na_sentinel)
# sort on
if sort:
sorter = self.uniques.to_array().argsort()
reverse_indexer = np.empty(len(sorter), dtype=np.intp)
reverse_indexer.put(sorter, np.arange(len(sorter)))
labels = reverse_indexer.take(labels, mode='clip')
labels[mask] = na_sentinel
self.count = len(self.uniques)
return labels
cdef class Int64Factorizer(Factorizer):
cdef public:
Int64HashTable table
Int64Vector uniques
def __cinit__(self, size_hint: int):
self.table = Int64HashTable(size_hint)
self.uniques = Int64Vector()
def factorize(self, const int64_t[:] values, sort=False,
na_sentinel=-1, na_value=None) -> np.ndarray:
"""
Returns
-------
ndarray[intp_t]
Examples
--------
Factorize values with nans replaced by na_sentinel
>>> fac = Int64Factorizer(3)
>>> fac.factorize(np.array([1,2,3]), na_sentinel=20)
array([0, 1, 2])
"""
cdef:
ndarray[intp_t] labels
if self.uniques.external_view_exists:
uniques = Int64Vector()
uniques.extend(self.uniques.to_array())
self.uniques = uniques
labels = self.table.get_labels(values, self.uniques,
self.count, na_sentinel,
na_value=na_value)
# sort on
if sort:
sorter = self.uniques.to_array().argsort()
reverse_indexer = np.empty(len(sorter), dtype=np.intp)
reverse_indexer.put(sorter, np.arange(len(sorter)))
labels = reverse_indexer.take(labels)
self.count = len(self.uniques)
return labels