Question

我正在尝试对元组列表进行排序。排序必须经过多个步骤。步骤是：

(1) Sort descending based on second element of tuple
(2) Sort descending based on string length of first element of tuple
(3) Sort ascending lexicographical order

因此，例如，列表：

[('ident', 3), (')', 2), ('(', 2), (';', 2), ('string', 1), ('}', 1), ('char', 1), ('=', 1), ('{', 1)]

应排序为：

[('ident', 3), ('(', 2),  (')', 2), (';', 2), ('string', 1), ('char', 1),  ('=', 1), ('{', 1), ('}', 1)]

我的尝试是：

theList = sorted(theList, key=lambda x: (x[1], len(x[0]), x[0]))

但这并没有产生所需的输出，我想要像：

theList = sorted(theList, key=lambda x: (x[1].descending(), len(x[0]).descending(), x[0].ascending()))

实现此目的的正确语法是什么？

Answer 1

这个怎么样？

>>> l = [('ident', 3), (')', 2), ('(', 2), (';', 2), ('string', 1), ('}', 1), ('char', 1), ('=', 1), ('{', 1)]
>>> sorted(l, key=lambda x: (-x[1], -len(x[0]), x[0]))
[('ident', 3), ('(', 2), (')', 2), (';', 2), ('string', 1), ('char', 1), ('=', 1), ('{', 1), ('}', 1)]

修改

从您的预期输出('=', 1), ('{', 1), ('}', 1)这是一个升序的词典顺序，请查看：

>>> c = ['}','=','{'] >>> map(ord, c) [125, 61, 123] >>> sorted(c) ['=', '{', '}'] #what you want to get >>> map(ord, sorted(c)) [61, 123, 125] #Ascending order

如果您希望按降序字典顺序排列，则可以执行以下操作：

>>> sorted(l, key=lambda x: (-x[1], -len(x[0]), -ord(x[0][0]))) [('ident', 3), (';', 2), (')', 2), ('(', 2), ('string', 1), ('char', 1), ('}', 1), ('{', 1), ('=', 1)]

Python - Multistep排序降序

1 个答案: