python 列表操作

列表的基本操作示例展示:

append

	功能:列表追加元素
	name = ['sd','dfdf','drer']
	name.append('sdsd')
	返回结果:name
			['sd', 'dfdf', 'drer', 'sdsd']

clear

	功能:情况列表元素
	name = ['sd','dfdf','drer']
	name.clear()
	返回结果:name
			 []

copy

	功能:浅拷贝,即只拷贝第一层的元素
	name = ['sd','dfdf','drer']
	li = ['ssd']
	li = name.copy()
	返回结果:li
			 ['sd', 'dfdf', 'drer']

	name = ['sd','dfdf','drer',['sddss','sdsdsd']]
	li = ['ssd']
	li = name.copy()
	返回结果:li
	['sd', 'dfdf', 'drer', ['sddss', 'sdsdsd']]

count

	功能:统计列表指定元素个数
	name = ['sd','dfdf','drer',['sddss','sdsdsd']]
	name.count('sd')
	返回结果:1
	li = ['sd','sdsds',['sd','dffdg',],]
	li.count('sd') #只统计第一层的元素个数
	返回结果:1

extend

	功能:追加字符元素或列表元素
	name = ['sd','dfdf','drer',['sddss','sdsdsd']]
	li = ['sd','sdsds',['sd','dffdg',],]
	name.extend('ss')
	返回结果:name
	['sd', 'dfdf', 'drer', ['sddss', 'sdsdsd'], 's', 's']
	name.extend('d')
	返回结果:name
	['sd', 'dfdf', 'drer', ['sddss', 'sdsdsd'], 's', 's', 'd']
	name.extend(li)
	返回结果:name
	['sd', 'dfdf', 'drer', ['sddss', 'sdsdsd'], 's', 's', 'd', 'sd', 'sdsds', ['sd', 'dffdg']]

index

	功能:定位列表中某元素
	name = ['sd','dfdf','drer',['sddss','sdsdsd']]
	name.index('sd')
	返回结果:0
	name.index('drer')
	返回结果:2
	返回结果:name.index('dr')  #当出现某元素不在列表中的时候会直接报错
			Traceback (most recent call last):
			  File "<stdin>", line 1, in <module>
			ValueError: 'dr' is not in list

insert

	功能:在指定索引位置的元素前面插入新的元素
	name = ['sd','dfdf','drer',['sddss','sdsdsd']]
	name.insert(3,'sd')
	返回结果:name
	['sd', 'dfdf', 'drer', 'sd', ['sddss', 'sdsdsd']]

pop

	功能:删除指定索引值的元素,返回值为当前删除的元素的值。不指定索引值,默认删除最后一个元素
	name = ['sd','dfdf','drer',['sddss','sdsdsd']]
	name.pop(3)
	返回结果:'sd'

remove

	功能:删除列表中指定的元素
	name = ['sd','dfdf','drer',['sddss','sdsdsd']]
	name.remove('sd')
	name
	返回结果:['dfdf', 'drer', ['sddss', 'sdsdsd']]

reverse

	功能:用于反向列表中元素。
	name = ['sd','dfdf','drer',['sddss','sdsdsd']]
	name.reverse()
	name
	返回结果:[['sddss', 'sdsdsd'], 'drer', 'dfdf', 'sd']

sort

	功能:对单层列表进行元素的排序
	name = ['sd','dfdf','drer',]
	name.sort()
	name
	返回结果:['dfdf', 'drer', 'sd']

	name = ['sd','dfdf','drer',['sddss','sdsdsd']]
	name.sort() #报错的
	Traceback (most recent call last):
	  File "<stdin>", line 1, in <module>
posted @ 2016-01-13 13:12  南非波波  阅读(1119)  评论(0编辑  收藏  举报