如何按键长度对字典进行排序，然后按值列表中的元素排序？

Question

我想先按键的长度对字典进行排序，然后再按值列表中的一个元素对字典进行排序。

到目前为止，我已经通过使用 lambda 排序接近了，但我遇到了问题，因为我的值是列表。文档不清楚如何处理这个问题（或至少据我所知）。

# What I have so far is:

d = {'ATCG': [1,2,3], 'ATTT':[1,3,5], 'GCT':[2,4,8], 'TCC': [4,5,6], 'AC': 
[7,8,9]}

value_sort = sorted(d.items(), key=lambda item: item[0]) 
# this only sorts by the first item in my list-- how do I sort by 
the third item in my list?

key_sort = sorted(value_sort, key=len, reverse=True) 
# sorts by largest length key

for k in key_sort:
     v = d[k[0]]
     print(k[0) + ":" + str(v))

我希望输出的样子是：

ATCG:[1,2,3]
ATTT:[1,3,5]
TCC:[4,5,6]
GCT:[2,4,8]
AC:[7,8,9]

排序是按最大键，然后按我的值列表中最小的第三个值。

编辑：我让按键更清晰

Answer 1

如果您将其分解为自己的函数而不是使用 lambda，那么准备您的关键函数会更容易。

您可能还想在排序后使用OrderedDict 来维护顺序：

from collections import OrderedDict

def get_keylength(v):
    key, values = v
    return len(key), values[0]

d = {'ATCG': [1,2,3], 'ATTT':[1,3,5], 'GCT':[2,4,8], 'TCC': [4,5,6], 'AC': [7,8,9]}
od = OrderedDict(sorted(d.items(), key=get_keylength, reverse=True))

OrderedDict([('ATCG', [1, 2, 3]), ('ATTT', [1, 3, 5]), ('TCC', [4, 5, 6]), (' GCT', [2, 4, 8]), ('AC', [7, 8, 9])])

如果你想要更清晰的输出，你可以使用pprint（漂亮的打印）：

import pprint
pprint.pprint(od)
OrderedDict([('ATCG', [1, 2, 3]),
             ('ATTT', [1, 3, 5]),
             ('TCC', [4, 5, 6]),
             ('GCT', [2, 4, 8]),
             ('AC', [7, 8, 9])])

# To get rid of OrderedDict you can convert back to a standard dictionary with `dict()`
pprint.pprint(dict(od))
{'AC': [7, 8, 9],
 'ATCG': [1, 2, 3],
 'ATTT': [1, 3, 5],
 'GCT': [2, 4, 8],
 'TCC': [4, 5, 6]}

Answer 2

这是一个按值的长度然后按值对字典进行排序的示例

示例 1：

d = {'ATCG':[1,2,3], 'ATTT':[1,3,5], 'TCC':[4,5,6], 'GCT':[2,4,8], 'AC':[7,8,9]}
# Use tuple to specify multiple criteria to sort upon
# i.e. first by length, then by key length, 
# then value (i.e. t[0] is key, t[1] is value)
value_sort = sorted(d.items(), key=lambda t: (len(t[0]), t[1]))

for k, v in value_sort:
  print(k, v)

输出

AC [7, 8, 9]
GCT [2, 4, 8]
TCC [4, 5, 6]
ATCG [1, 2, 3]
ATTT [1, 3, 5]

示例 2：

d = {"one": [(1,3),(1,4)], 
        "two": [(1,2),(1,2),(1,3)], 
        "three": [(1,1)]}

# Use tuple to specify multiple criteria to sort upon
# i.e. first by length, then by value
# t[1] is value of dictionary entry
value_sort = sorted(d.items(), key=lambda t: (len(t[1]), t[1]))

for k, v in value_sort:
  print(k, v)

输出

three [(1, 1)]
one [(1, 3), (1, 4)]
two [(1, 2), (1, 2), (1, 3)]