5.Python入门到精通
从列表中获取元素跟数组一样，我们可以通过元素的索引值（index）从列表获取单个元素，注意，列表索引值是从 0 开始的。
['u', 'a', 'b', 'c', 'd', 'e', 'k', 'f']
>>> member
'u'
>>> member
'a'
>>>
>>> temp = member
>>> member = member
>>> member
['a', 'a', 'b', 'c', 'd', 'e', 'k', 'f']
>>> member = temp
>>> member
['a', 'u', 'b', 'c', 'd', 'e', 'k', 'f']
>>>
从列表删除元素
remove()
>>> member.remove('b')
>>> member
['a', 'u', 'c', 'd', 'e', 'k', 'f']
>>>
del
>>> del member
>>> member
['u', 'c', 'd', 'e', 'k', 'f']
>>>
pop()
>>> member.pop()
'f'
>>> member
['u', 'c', 'd', 'e', 'k']
>>> name=member.pop()
>>> name
'k'
>>> member.pop(2)
'd'
>>>
列表分片（Slice）
利用索引值，每次我们可以从列表获取一个元素，但是我们总是贪心的，如果一次性需要获取多个元素，有没有办法实现呢？利用列表分片，我们可以简单的实现这个要求。
>>> member
['c', 'e']
>>>
>>> member
['u', 'c', 'e']
>>> member[:3]
['u', 'c', 'e']
>>> member[:]
['u', 'c', 'e']
>>> member
['c', 'e']
>>>
列表的一些常用操作符
比较操作符
>>> list1 =
>>> list2 =
>>> list1 > list2
False
>>> list1 =
>>> list2 =
>>> list1 > list2
False
>>> list3=
逻辑操作符
>>> (list1 < list2) and (list1 == list3)
True
连接操作符
>>> list4 = list1 + list2
>>> list4
>>> list1 + 'x'
Traceback (most recent call last):
File "<pyshell#79>", line 1, in <module>
list1 + 'x'
TypeError: can only concatenate list (not "str") to list
重复操作符
>>> list3 * 3
>>> list3 *= 3
>>> list3
>>> list3 *= 5
>>> list3
>>>
成员关系操作符
>>> 123 in list3
True
>>> 'd' not in list3
True
>>> 123 not in list3
False
>>>
>>> list5 = ,456]
>>> 'd' in list5
False
>>> 'd' in list5
True
>>> list5
'u'
>>>
列表的小伙伴们
>>> dir(list)
['__add__', '__class__', '__contains__', '__delattr__', '__delitem__', '__dir__', '__doc__', '__eq__', '__format__', '__ge__', '__getattribute__', '__getitem__', '__gt__', '__hash__', '__iadd__', '__imul__', '__init__', '__init_subclass__', '__iter__', '__le__', '__len__', '__lt__', '__mul__', '__ne__', '__new__', '__reduce__', '__reduce_ex__', '__repr__', '__reversed__', '__rmul__', '__setattr__', '__setitem__', '__sizeof__', '__str__', '__subclasshook__', 'append', 'clear', 'copy', 'count', 'extend', 'index', 'insert', 'pop', 'remove', 'reverse', 'sort']
>>> list3.count(123)
15
>>> list3.index(123)
0
>>> list3.index(123,3,7)
4
>>> list3.reverse()
>>> list3
>>> list6 =
>>> list6.sort()
>>> list6
>>> list6.sort(reverse=True)
>>> list6
>>>
关于分片“拷贝”概念的补充
>>> list7 = list6[:]
>>> list7
>>> list8 = list6
>>> list8
>>> list6.sort()
>>> list6
>>> list7
>>> list8
>>>
元组：戴上了枷锁的列表
由于和列表是近亲关系，所以元组和列表在实际使用上是非常相似的。
我们这节课主要通过讨论元组和列表到底有什么不同来学习元组，酱紫大家就不会觉得老是重复一样的内容。
我们主要从以下几个点来讨论学习：
创键和访问一个元组
>>> temp=(1)
>>> temp
1
>>> type(temp)
<class 'int'>
>>> temp2=2,3,4
>>> type(temp2)
<class 'tuple'>
>>> temp = []
>>> type (temp)
<class 'list'>
>>> temp = ()
>>> type(temp)
<class 'tuple'>
>>> temp = (1,)
>>> type(temp)
<class 'tuple'>
>>>
>>> temp = 1,
>>> type(temp)
<class 'tuple'>
>>> 8 * (8)
64
>>> 8 * (8,)
(8, 8, 8, 8, 8, 8, 8, 8)
>>>
更新和删除一个元组
>>> temp = ('d','c','a','b')
>>> temp = temp[:3] + ('f',) + temp
>>> temp
('d', 'c', 'a', 'f', 'b')
>>> del temp
>>> temp
Traceback (most recent call last):
File "<pyshell#148>", line 1, in <module>
temp
NameError: name 'temp' is not defined
>>>
元组相关的操作符
>>> str1 = 'I love Python'
>>> str1[:6]
'I love'
>>> str1
'I love Python'
>>> str1
' '
>>> str1
'e'
>>> str1[:6] + 'inserstr' + str1
'I loveinserstr Python'
>>> str1
'I love Python'
>>>
字符串：各种奇葩的内置方法
>>> str2 = 'ivwdcwso'
>>> str2.capitalize()
'Ivwdcwso'
>>> str2='IvwDcwSo'
>>> str2.casefold()
'ivwdcwso'
>>> str2
'IvwDcwSo'
>>> str2.center(40)
' IvwDcwSo '
>>> str2.count('w')
2
>>> str2.endswith('w')
False
>>> str2.endswith('o')
True
>>> str3 = 'I\tlove\tPython!'
>>> str3.expandtabs()
'I love Python!'
>>> str3.find('efc')
-1
>>> str3.find('o')
3
>>>
>>> str3
'I\tlove\tPython!'
>>> str3.istitle()
False
>>> str3.join('123')
'1I\tlove\tPython!2I\tlove\tPython!3'
>>>
>>> str6 = ' I love Python!'
>>> str6.lstrip()
'I love Python!'
>>> str6 = 'i love python'
>>> str6.partition('ov')
('i l', 'ov', 'e python')
>>> str6
'i love python'
>>> str6.replace('python','Python')
'i love Python'
>>>
>>> str6.split()
['i', 'love', 'python']
>>>
>>> str6.split('i')
['', ' love python']
>>>
>>> str7 = ' aaaa '
>>> str7.strip()
'aaaa'
>>> str7=str7.strip()
>>> str7
'aaaa'
>>>
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