Question

我想标记连接组件的所有元素。图表的链接使用字典字典格式化。具有递归的算法似乎很快，不幸的是对于较大的图形，最大递归深度产生问题并且我不希望每次都增加最大递归长度。你知道如何重写这段代码，深度不再麻烦了吗？

import numpy as np
def find_components(dists):

    N = len(dists.keys())
    labels = np.zeros(N, dtype = np.int) - 1
    n = 0
    steps = 0 

    def walk(j):
        for k in dists[j].keys():
            if (labels[k] == -1):
                labels[k] = labels[j]
                walk(k)

    remains = (labels == -1)
    while n < N:
        i = np.arange(0,N,1)[remains][np.random.randint(0,N - n)]
        labels[i] = i
        walk(i)
        remains = (labels == -1)
        n = N - len(np.nonzero(remains)[0])
    unique = np.unique(labels)
    labels_ = np.zeros(N, dtype = np.int) - 1
    for i, label in enumerate(unique):
        labels_[labels == label] = i
    return labels_

Answer 1

将walk()从递归函数转换为迭代版本：

import collections

def walk(j):
    lifo = collections.deque(j)

    while lifo:
        for k in dists[lifo.pop()].keys():
            if labels[k] == -1:
               labels[k] = labels[j]
               lifo.append(k)

在连通分量分析中避免最大递归深度？

1 个答案: