python基础训练题1-列表操作

1,在列表末尾添加一个值

>>> l = [ 10, 20 ]
>>> l
[10, 20]
>>> l.append( 'ghostwu' )
>>> l
[10, 20, 'ghostwu']
>>> 

2,在列表的某个值前面插入一项,在'ghostwu'前面插入一项值'wukong'

>>> l
[10, 20, 'ghostwu']
>>> l.insert(  2, 'wukong' )
>>> l
[10, 20, 'wukong', 'ghostwu']
>>> 

3,修改列表的某项值

>>> l
[10, 20, 'wukong', 'ghostwu']
>>> l[0] = 100
>>> l
[100, 20, 'wukong', 'ghostwu']
>>> 

4,删除列表中的某个值

>>> l
[100, 20, 'wukong', 'ghostwu']
>>> l.pop( 0 )
100
>>> l
[20, 'wukong', 'ghostwu']
>>> 
>>> l
[20, 'wukong', 'ghostwu']
>>> del l[2]
>>> l
[20, 'wukong']
>>> 
>>> l
[20, 'wukong', 'ghostwu', 'ghostwu', 'ghostwu']
>>> l.remove( 'ghostwu' )
>>> l
[20, 'wukong', 'ghostwu', 'ghostwu']
>>> 

5,对一个列表进行排序

>>> l = [ 3, 2, -1, 0, 10, -8, 100 ]
>>> l
[3, 2, -1, 0, 10, -8, 100]
>>> l.sort()
>>> l
[-8, -1, 0, 2, 3, 10, 100]
>>> 

6,从一个已知的列表,用两种方式生成一个新的列表

>>> a = [1, 2, 3]
>>> b = [4, 5, 6]
>>> a
[1, 2, 3]
>>> b
[4, 5, 6]
>>> c = a + b
>>> c
[1, 2, 3, 4, 5, 6]
>>>
>>> a = [1,2,3]
>>> b = [4,5,6]
>>> c = []
>>> a.extend( b )
>>> a
[1, 2, 3, 4, 5, 6]
>>> c.extend( a )
>>> c
[1, 2, 3, 4, 5, 6]
>>> 

7,从列表的后面取出元素,一种是切片操作,另一种是pop+append组合

>>> a = [1,2,3,4,5]
>>> a[-1:-3:-1]
[5, 4]
>>> 
>>> a
[1, 2, 3, 4, 5]
>>> l=[]
>>> l.append( a.pop() )
>>> l.append( a.pop() )
>>> l
[5, 4]
>>> 

8,判断一个数在不在列表中

>>> a
[1, 2, 3]
>>> 1 in a 
True
>>> '1' in a
False

9,用列表推倒表达式,取出列表中所有的奇数

>>> a = [10, 13, 21, 22, 50, 56, 32, 31, 19]
>>> res = [b for b in a if b % 2 != 0 ]
>>> res
[13, 21, 31, 19]
>>>

 根据列表[ 10, 13, 21, 22, 50, 56 ]生成字符串[ 'ghostwu10', 'ghostwu13', 'ghostwu21' ]

>>> l = [ 10, 13, 21, 22, 50, 56 ]
>>> s = ["ghostwu %s" % x for x in l[0:3] ]
>>> s
['ghostwu 10', 'ghostwu 13', 'ghostwu 21']
>>> 

对列表的每一项+2,生成新的列表

>>> l
[10, 13, 21, 22, 50, 56]
>>> n = [ x + 2 for x in l ]
>>> n
[12, 15, 23, 24, 52, 58]
>>>

10,用range和推导式生成[11,22,33,44,55,66]这样的列表

>>> l = []
>>> l = range( 11, 67, 11 )
>>> l
[11, 22, 33, 44, 55, 66]
>>> 
>>> l = []
>>> l = [ x * 11 for x in range( 1, 7 ) ]
>>> l
[11, 22, 33, 44, 55, 66]
>>> 

 

posted @ 2018-03-27 21:47  ghostwu  阅读(982)  评论(0编辑  收藏  举报
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