我收到了错误信息
Cannot convert Python object argument to type 'f_type'
objective
但是,一般来说:不,你不能给你的目标函数一个类型说明符来加速它。一般的Python可调用函数比C函数指针携带更多的信息(例如引用计数、任何闭包捕获变量的细节等)。
一种可能的替代方法是继承
cdef class
cdef
功能,因此您至少可以在特定情况下获得适当的性能:
# an abstract function pointer class
cdef class FPtr:
cdef double function(self,double[:] x) except? 0.0:
# I'm assuming you might want to pass exceptions back to Python - use 0.0 to indicate that there might have been an error
raise NotImplementedError()
# an example class that inherits from the abstract pointer type
cdef class SumSq(FPtr):
cdef double function(self,double[:] x) except? 0.0:
cdef double sum=0.0
for i in range(x.shape[0]):
sum += x[i]**2
return sum
# an example class that just wraps a Python callable
# this will be no faster, but makes the code generically usable
cdef class PyFPtr(FPtr):
cdef object f
def __init__(self,f):
self.f = f
cdef double function(self,double[:] x) except? 0.0:
return self.f(x) # will raise an exception if the types don't match
def example_function(FPtr my_callable):
import numpy as np
return my_callable.function(np.ones((10,)))
使用这个
example_function(SumSq())
example_function(PyFPtr(lambda x: x[0]))
按预期工作(可调用中没有Cython速度);
example_function(PyFPtr(lambda x: "hello"))
