PROSAGA码农传奇-智慧城市-在项目数组中包含的元素上切片

在项目数组中包含的元素上切片

作者: 明天会更好
发布时间: 2025-03-01 06:30:43 (2天前)
转自：

<div class =“post-text”itemprop =“text”>
  <P>
    如果我正确理解你的问题，正如评论中所谈到的那样，应该这样做
  </p>
   <pre>
    <code>
      from pprint import pprint

def slice_dict(d,a, b):
  big_list = []
  ret_dict = {}
  # Make one big list of all numbers, tagging each number with the key
  # of the dict they came from.
  for k, v in d.iteritems():
    for n in v:
      big_list.append({k:n})
  # Slice it
  sliced = big_list[a:b]

# Put everything back in order
  for k, v in d.iteritems():
    for subd in sliced:
      for subk, subv in subd.iteritems():
        if k == subk:
          if k in ret_dict:
            ret_dict[k].append(subv)
          else:
            ret_dict[k] = [subv]

return ret_dict

d = {
  'a': [1, 2, 3, 4],
  'b': [5, 6, 7, 8, 9],
  'c': [10, 11, 12, 13, 14]
}

x = slice_dict(d, 3, 11)
pprint(x)

</code>
  </pre>
  <HR />
   <pre>
    <code>
      $ python slice.py 
{'a': [4], 'b': [5, 6], 'c': [10, 11, 12, 13, 14]}

</code>
  </pre>
  <P>
    输出与示例输出略有不同，但这是因为dict在传递给函数时没有排序。这是a-c-b，这就是为什么b在6处切断而c没有切断的原因
  </p>
</DIV>