python的排序函数sort,sorted在列表排序和字典排序中的应用详解和举例
python 列表list中内置了一个十分有用的排序函数sort,sorted,它可以用于列表的排序,以下是例子。
- a = [5,2,1,9,6]
-
- >>> sorted(a)
- [1, 2, 5, 6, 9]
-
- >>> sorted(a,reverse = True)
- [9, 6, 5, 2, 1]
-
- >>> a.sort()
- >>> a
- [1, 2, 5, 6, 9]
-
- >>> a.sort(reverse = True)
- >>> a
- [9, 6, 5, 2, 1]
-
- 注意,a.sort() 已改变其结构,b = a.sort() 是错误的写法!
-
>>> b = ['aa','BB','bb','zz','CC']
- >>> sorted(b)
- ['BB', 'CC', 'aa', 'bb', 'zz']
-
- >>> c =['CCC', 'bb', 'ffff', 'z']
- >>> sorted(c,key=len)
- ['z', 'bb', 'CCC', 'ffff']
-
- >>> d =['CCC', 'bb', 'ffff', 'z']
- >>> sorted(d,key = str.lower )
- ['bb', 'CCC', 'ffff', 'z']
-
- >>> def lastchar(s):
- return s[-1]
- >>> e = ['abc','b','AAz','ef']
- >>> sorted(e,key = lastchar)
- ['b', 'abc', 'ef', 'AAz']
-
- >>> f = [{'name':'abc','age':20},{'name':'def','age':30},{'name':'ghi','age':25}]
- >>> def age(s):
- return s['age']
- >>> ff = sorted(f,key = age)
-
- [{'age': 20, 'name': 'abc'}, {'age': 25, 'name': 'ghi'}, {'age': 30, 'name': 'def'}]
-
- >>> f2 = sorted(f,key = lambda x:x['age'])
本文转自 lover00751CTO博客,原文链接:http://blog.51cto.com/wangwei007/1100742,如需转载请自行联系原作者