我正在尝试在 cython 中实现通用排序算法。因此，我创建了以下模块，该模块在类中实现了堆排序算法sorter_t：
# file general_sort_c.pyx
from libc.stdint cimport int32_t
cdef bint bint_true = 1
cdef bint bint_false = 0
cdef class sorter_t:
cdef object sortable_object
def __init__(self,sortable_object):
self.sortable_object = sortable_object
cpdef sort_c(self):
"""
https://en.wikipedia.org/wiki/Heapsort
"""
cdef int32_t end
cdef int32_t count = self.sortable_object.num_elements_int32
self.heapify_c(count)
end = count-1
while end > 0:
self.sortable_object.swap_c(0,end)
end = end - 1
self.siftDown_c(0,end)
cdef heapify_c(self,int32_t count):
cdef int32_t start = (count - 2)/2
while start >= 0:
self.siftDown_c(start, count-1)
start -= 1
cdef siftDown_c(self,int32_t start, int32_t end):
cdef int32_t root = start
cdef int32_t swap
cdef int32_t child
while root * 2 + 1 <= end:
child = root * 2 + 1
swap = root
# if "swap" < "child" then ...
if self.sortable_object.lt_c(swap,child) == 1:
swap = child
if child+1 <= end and self.sortable_object.lt_c(swap,child+1) == 1:
swap = child + 1
if swap != root:
self.sortable_object.swap_c(root,swap)
root = swap
else:
return
当您定义一个类型的对象时，sorter_t您必须提供一个sortable_object具有自己特定实现的 cdef 函数lt_c（用于比较一个元素是否小于另一个）和swap_c（用于交换元素）。
例如，以下代码将定义并sortable_object从列表中创建一个，并将使用该来测试“sorter_t”的实现sortable_object。
import numpy
cimport numpy
from libc.stdint cimport int32_t
import general_sort_c
cdef class sortable_t:
cdef public int32_t num_elements_int32
cdef int32_t [:] mv_lista
def __init__(self,int32_t [:] mv_lista):
self.num_elements_int32 = mv_lista.shape[0]
self.mv_lista = mv_lista
cdef public bint lt_c(self, int32_t left, int32_t right):
if self.mv_lista[left] < self.mv_lista[right]:
return 1 # True
else:
return 0 # False
cdef public bint gt_c(self, int32_t left, int32_t right):
if self.mv_lista[left] > self.mv_lista[right]:
return 1 # True
else:
return 0 # False
cdef public swap_c(self, int32_t left, int32_t right):
cdef int32_t tmp
tmp = self.mv_lista[right]
self.mv_lista[right] = self.mv_lista[left]
self.mv_lista[left] = tmp
def probar():
lista = numpy.array([3,4,1,7],dtype=numpy.int32)
cdef int32_t [:] mv_lista = lista
cdef sortable = sortable_t(mv_lista)
cdef sorter = general_sort_c.sorter_t(sortable)
sorter.sort_increasing_c()
print list(lista)
编译这两个.pyx文件并在 IPython 控制台中运行以下命令后，出现以下错误：
In [1]: import test_general_sort_c as tgs
In [2]: tgs.probar()
...
general_sort_c.sorter_t.siftDown_increasing_c (general_sort_c.c:1452)()
132
133 #if mv_tnet_time[swap] < mv_tnet_time[child]:
--> 134 if self.sortable_object.lt_c(swap,child) == bint_true:
135 swap = child
136
AttributeError: 'test_general_sort_c.sortable_t' object has no attribute 'lt_c'
lt_c所以，问题是从模块中的代码看不到函数的实现general_sort_c.pyx。如果我lt_c使用cpdef而不是cdef它来定义函数，它将起作用，但是你有很多 Python 开销。如何以cdef（“纯 C”）方式调用此函数？