非常慢的cython课程?

时间:2012-05-01 07:10:33

标签: python performance class cython

此代码包含cython类:

cdef class Bench:
    cdef long n
    def __cinit__(self, long n):
    self.n = n

    cpdef int factors(self):
        n = self.n
        cdef int fac = 0
        cdef unsigned long i
        for i in range(2, n):
            if n % i == 0:
                fac += 1

        return fac


if __name__ == "__main__":
    print "hw"

在编译成python扩展后我这样调用:

from time import time
t1 = time()
import factors_class
ben = factors_class.Bench(1000000007)
print ben.factors()
t2 = time()
print t2 - t1

并打印出207.374788046(秒)

但是纯python版本(只有函数和对它的调用)运行在~77s 没有类结构的cython代码在~10.2s中运行

cython中的无类版本:

cdef int factors(unsigned long n):
    cdef int fac = 0
    cdef unsigned long i
    for i in range(2, n):
        if n % i == 0:
            fac += 1

     return fac


print factors(1000000007)

if __name__ == "__main__":
    print "hw"

Python版本:

def factors(n):
    fac = 0
    for i in xrange(2, n):
        if n % i == 0:
            fac += 1

    return fac

print factors(10000007)

我想在我的库中使用cython类,但是与cython中的函数式编程相比,它们似乎非常慢。显然我的cython类代码有问题。 我怎样才能提高它的速度?

总结基准测试结果:

Cython课程:206s

Cython:10.2s

python:77s

1 个答案:

答案 0 :(得分:8)

声明局部变量n的类型:

cdef long n = self.n