小编use*_*189的帖子

例如，如果我有一个数组：

A = (0,2,3,4,5,2,1,2,3,4,5,6,7,8,7,6,5,4,5,6)

可以看出有4个转折点。（在 A[4]、A[6]、A[13]、A[17]）

如何使用python返回转折点的数量？

import numpy as np
import scipy.integrate as SP
import math

def turningpoints(A):
    print A
    N = 0
    delta = 0
    delta_prev = 0
    for i in range(1,19):
        delta = A[i-1]-A[i]       #Change between elements
        if delta < delta_prev:    #if change has gotten smaller
            N = N+1               #number of turning points increases
        delta_prev = delta        #set the change as the previous change
    return N

if __name__ == "__main__":
    A  = np.array([0,2,3,4,5,2,1,2,3,4,5,6,7,8,7,6,5,4,5,6])
    print turningpoints(A)

目前，这个系统是有缺陷的，当然不是很优雅。有任何想法吗？