按值排序字典然后键 [英] Sorting a dictionary by value then key

问题描述

我可以按键或值排序，但我需要在一行中按值排序，然后是键.为了更好地解释这一点，我可以向您展示我的问题:

dict = {'apple': 2, 'banana': 3, 'almond':2 , 'beetroot': 3, 'peach': 4}

我希望我的输出按它们的值降序排序，然后按它们的键(按字母顺序)升序 (A-Z).导致这样一个列表:

输出:['peach', 'banana', 'beetroot', 'almond', 'apple']

到目前为止我知道的唯一方法是:

[v[0] for v in sorted(dict.items(), key=lambda(k,v): (v,k))]

输出:['almond', 'apple', 'banana', 'beetroot', 'peach']

因此它按升序对值进行了排序，并按字母顺序(A-Z)对键进行了排序.所以如果我扭转这个:

[v[0] for v in sorted(dict.items(), key=lambda(k,v): (v,k), reverse=True)]

输出:['peach', 'beetroot', 'banana', 'apple', 'almond']

它已按降序对值进行排序，并按字母顺序(Z-A)对键进行排序.

有没有一种方法可以按降序对值进行排序，按升序(即 A-Z)对键进行排序并获得我上面显示的输出?

解决方案

您需要利用值是数字这一事实.

<预><代码>>>>[v[0] for v in sorted(d.iteritems(), key=lambda(k, v): (-v, k))]['桃子'、'香蕉'、'甜菜根'、'杏仁'、'苹果']

I can sort by key or value, but I need it sorted by value, then key, in one line. To explain this better I can show you my problem:

dict = {'apple': 2, 'banana': 3, 'almond':2 , 'beetroot': 3, 'peach': 4}

I want my output to be sorted descending by their value and then ascending (A-Z) by their key (alphabetically). Resulting in such a list:

With the output of: ['peach', 'banana', 'beetroot', 'almond', 'apple']

The only way I know how to do it so far is:

[v[0] for v in sorted(dict.items(), key=lambda(k,v): (v,k))]

With the output of: ['almond', 'apple', 'banana', 'beetroot', 'peach']

So it has sorted the values in ascending order and the keys alphabetically in ascending order (A-Z). So if I reverse this:

[v[0] for v in sorted(dict.items(), key=lambda(k,v): (v,k), reverse=True)]

With the output of: ['peach', 'beetroot', 'banana', 'apple', 'almond']

It has sorted the values in descending order and the keys alphabetically in descending order (Z-A).

Is there a way I can sort the values in descending order and the keys in ascending order (i.e. A-Z) and get the output I showed above?

解决方案

You need to take advantage of the fact that the values are numbers.

>>> [v[0] for v in sorted(d.iteritems(), key=lambda(k, v): (-v, k))]
['peach', 'banana', 'beetroot', 'almond', 'apple']

这篇关于按值排序字典然后键的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！