如何在python中执行辅助排序?

If i have a list of numbers [4,2,5,1,3] I want to sort it first by some function f and then for numbers with the same value of f i want it to be sorted by the magnitude of the number.

如果我有一个数字列表[4,2,5,1,3]我想先用某个函数f对它进行排序，然后对于f值相同的数字，我想用数字的大小对它排序。

This code does not seem to be working.

这段代码似乎不能工作。

list5 = sorted(list5)
list5 = sorted(list5, key = lambda vertex: degree(vertex))

Secondary sorting first: list5 is sorted based on magnitude. Primary sorting next: list5 is sorted based on some function of the numbers.

次要排序首先:清单5是根据大小排序的。接下来是主排序:清单5是根据数字的某个函数排序的。

3 个解决方案

#1

Sort it by a (firstkey, secondkey) tuple:

按(firstkey, secondkey)元组排序:

sorted(list5, key=lambda vertex: (degree(vertex), vertex))

#2

From the Python 3 docs on sorting

来自Python 3文档的排序

from operator import itemgetter, attrgetter
student_objects = [
    Student('john', 'A', 15),
    Student('jane', 'B', 12),
    Student('dave', 'B', 10),
]
student_tuples = [
    ('john', 'A', 15),
    ('jane', 'B', 12),
    ('dave', 'B', 10),
]

#The operator module functions allow multiple levels of sorting. For example, to sort by grade then by age:

sorted(student_tuples, key=itemgetter(1,2))
sorted(student_objects, key=attrgetter('grade', 'age'))

#3

On a phone, but youcan sort by tuple.

在电话上，你可以按元组排序。

sorted(list5, lambda x: (degree(x),x))

Don't forget the reverse flag if you need it.

如果需要，不要忘记反向标志。

#1