将值添加到 defaultdict set breaking on 128

Question

一旦我的地址达到值 128，就会出现问题，它会停止将新值放在嵌套字典的末尾。而是再次从头开始订购。为什么要这样做？

result.setdefault(fan_definitions_name, set()).add(int(address))

我正在循环的数据结构如下所示 ->

list_address_of_selected_fans = [[101, 'standard fan definition1', 'JVEC-SP'],[102, 'standard fan definition1', 'JVEC-SP']]

编辑：这是我提供输入的运行nable 示例。你可以直接运行这个例子（我用的是python 3.8.2）

list_address_of_selected_fans = [[101, 'standard fan definition1', 'JVEC-SP'],
                                 [102, 'standard fan definition1', 'JVEC-SP'],
                                 [103, 'standard fan definition1', 'JVEC-SP'],
                                 [104, 'standard fan definition1', 'JVEC-SP'],
                                 [105, 'standard fan definition1', 'JVEC-SP'],
                                 [106, 'standard fan definition1', 'JVEC-SP'],
                                 [107, 'standard fan definition1', 'JVEC-SP'],
                                 [108, 'standard fan definition1', 'JVEC-SP'],
                                 [109, 'standard fan definition1', 'JVEC-SP'],
                                 [110, 'standard fan definition1', 'JVEC-SP'],
                                 [111, 'standard fan definition1', 'JVEC-SP'],
                                 [112, 'standard fan definition1', 'JVEC-SP'],
                                 [113, 'standard fan definition1', 'JVEC-SP'],
                                 [114, 'standard fan definition1', 'JVEC-SP'],
                                 [115, 'standard fan definition1', 'JVEC-SP'],
                                 [116, 'standard fan definition1', 'JVEC-SP'],
                                 [117, 'standard fan definition1', 'JVEC-SP'],
                                 [118, 'standard fan definition1', 'JVEC-SP'],
                                 [119, 'standard fan definition1', 'JVEC-SP'],
                                 [120, 'standard fan definition1', 'JVEC-SP'],
                                 [121, 'standard fan definition1', 'JVEC-SP'],
                                 [122, 'standard fan definition1', 'JVEC-SP'],
                                 [123, 'standard fan definition1', 'JVEC-SP'],
                                 [124, 'standard fan definition1', 'JVEC-SP'],
                                 [125, 'standard fan definition1', 'JVEC-SP'],
                                 [126, 'standard fan definition1', 'JVEC-SP'],
                                 [127, 'standard fan definition1', 'JVEC-SP'],
                                 [128, 'standard fan definition1', 'JVEC-SP'],
                                 [129, 'standard fan definition1', 'JVEC-SP'],
                                 [130, 'standard fan definition1', 'JVEC-SP'],
                                 [131, 'standard fan definition1', 'JVEC-SP'],
                                 [132, 'standard fan definition1', 'JVEC-SP'],
                                 [133, 'standard fan definition1', 'JVEC-SP'],
                                 [134, 'standard fan definition1', 'JVEC-SP'],
                                 [135, 'standard fan definition1', 'JVEC-SP'],
                                 [136, 'standard fan definition1', 'JVEC-SP'],
                                 [137, 'standard fan definition1', 'JVEC-SP'],
                                 [138, 'standard fan definition1', 'JVEC-SP'],
                                 [139, 'standard fan definition1', 'JVEC-SP'],
                                 [140, 'standard fan definition1', 'JVEC-SP'],
                                 [141, 'standard fan definition1', 'JVEC-SP'],
                                 [142, 'standard fan definition1', 'JVEC-SP'],
                                 [143, 'standard fan definition1', 'JVEC-SP'],
                                 [144, 'standard fan definition1', 'JVEC-SP'],
                                 [145, 'standard fan definition1', 'JVEC-SP'],
                                 [146, 'standard fan definition1', 'JVEC-SP'],
                                 [147, 'standard fan definition1', 'JVEC-SP'],
                                 [148, 'standard fan definition1', 'JVEC-SP'],
                                 [149, 'standard fan definition1', 'JVEC-SP'],
                                 [150, 'standard fan definition1', 'JVEC-SP']]
result = {}

for address, fan_definitions_name, fan_type in list_address_of_selected_fans:
    result.setdefault(fan_definitions_name, set()).add(int(address))

print(result)

结果为 -> {'standard fan definition1': {128, 129, 130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140, 141, 142, 143, 144, 145, 146, 147, 148, 149, 150, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127}}

为什么要这样做？这些数字应该按顺序排列，例如它们最初位于 list_address_of_selected_fans 变量中。

编辑2：这是显示问题的实时代码 https://repl.it/talk/share/adding-values-to-defaultdict-set-breaking-on-128/122013

Answer 1

set() 对象是无序集合（参见https://docs.python.org/3.8/library/stdtypes.html#set-types-set-frozenset）

为了您的目的，如果您希望它们按它们最初出现的顺序排列并且您将允许重复，您可以将 set() 和 add() 换成 list() 和 append()：

for address, fan_definitions_name, fan_type in list_address_of_selected_fans:
    result.setdefault(fan_definitions_name, list()).append(int(address))

如果您想忽略重复，那么除了列表之外，您还必须通过创建集合来检查这些...:[=14=]

result = {}
result_sets = {}

for address, fan_definitions_name, fan_type in list_address_of_selected_fans:
    iaddress = int(address)
    prev_set = result_sets.get(fan_definitions_name, set())
    if (iaddress not in prev_set):
        result.setdefault(fan_definitions_name, list()).append(iaddress)
        result_sets.setdefault(fan_definitions_name, set()).add(iaddress)

或者，如果您想将所有内容都放在一个变量中并使用更少的代码，您可以像这样使用 OrderedDict 来实现：

from collections import OrderedDict
result = {}
for address, fan_definitions_name, fan_type in list_address_of_selected_fans:
    result.setdefault(fan_definitions_name, OrderedDict())[int(address)] = None

print(result['standard fan definition1'].keys())

将值添加到 defaultdict set breaking on 128

adding values to defaultdict set breaking on 128

python

dictionary

set

defaultdict

setdefault