列表

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代码实现

List = ['Objective-c','Swift','Python','Java','C++','C']

print('List now content:',List)

print('List length is',len(List))

for item in List:

print('List content: ',item,end=' \n')

List.append('Ruby')//追加元素

print('List now content:',List)

List.sort()//排序

print('List sort content:',List)

print('List first item:',List[0])

firstItem = List[0]

del List[0]//删除元素

print('firstItem is:',firstItem)

print('List finally is:',List)

运行结果

List now content: ['Objective-c', 'Swift', 'Python', 'Java', 'C++', 'C']

List length is 6

List content: Objective-c

List content: Swift

List content: Python

List content: Java

List content: C++

List content: C

List now content: ['Objective-c', 'Swift', 'Python', 'Java', 'C++', 'C', 'Ruby']

List sort content: ['C', 'C++', 'Java', 'Objective-c', 'Python', 'Ruby', 'Swift']

List first item: C

firstItem is: C

List finally is: ['C++', 'Java', 'Objective-c', 'Python', 'Ruby', 'Swift']

列表是可变的，字符串是不可变的

元组 Tuple

元组是不可变的，不可以编辑或更改元组

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代码实现

mouth = ('day 1','day 2','day 3','day 4','day 5')

print('mouth length is :',len(mouth))

new_mouth = mouth,'day 11','day'

print('new mouth is :',new_mouth)

print('old mouth is :',new_mouth[0])

print('last item of old mouth is :',new_mouth[0][len(mouth)-1])

print('new mouth length is :',len(new_mouth))

运行结果

mouth length is : 5

new mouth is : (('day 1', 'day 2', 'day 3', 'day 4', 'day 5'), 'day 11', 'day')

old mouth is : ('day 1', 'day 2', 'day 3', 'day 4', 'day 5')

last item of old mouth is : day 5

new mouth length is : 3

new mouth actually length is 7

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包含一个元素的元组

mouth = ('day1', )//必须在第一个元素后面加逗号，以便程序区分

字典

键值对，key-value。key 只能是不可变得对象，value 是可变和不可变都可以。

样式：dict = {name:joy,age:18}

示例代码

student = {

'name' : 'joy',

'age' : 18,

'stuNo': '036',

'birth':'1994-11-24',

}

print('student message is:',student)

print('student name is:',student['name'])

del student['birth']

print('now student message is {}'.format(student))

for name, age in student.items():

print('name:{} and age :{}'.format(name,age))

student['place'] = 'BeiJing'

if 'place' in student:

print('now student message is {}'.format(student))

输出结果

student message is: {'name': 'joy', 'age': 18, 'stuNo': '036', 'birth': '1994-11-24'}

student name is: joy

now student message is {'name': 'joy', 'age': 18, 'stuNo': '036'}

name:name and age :joy

name:age and age :18

name:stuNo and age :036

now student message is {'name': 'joy', 'age': 18, 'stuNo': '036', 'place': 'BeiJing'}

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序列

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代码实现

List = ['Objective-c','Swift','Python','Java','C++','C']

new_item = 'single Language'

print('item 0 is:',List[0])

print('item 3 is:',List[3])

print('item -2 is:',List[-2])

print('item -1 is:',List[-1])

print('new_item is:',new_item[7])

print('===========================')

# 列表截取

print('item 1-3:',List[1:3])

print('item 2-end is:',List[2:])

print('item 1to-1 is:',List[1:-1])

print('item 0-end is:',List[:])

# 字符串截取

print('new_item 7-end is:',new_item[7:])

print('item 0-4:',new_item[0:4])

print('item 4to-4:',new_item[4:-4])

输出结果

item 0 is: Objective-c

item 3 is: Java

item -2 is: C++

item -1 is: C

new_item is: L

===========================

item 1-3: ['Swift', 'Python']

item 2-end is: ['Python', 'Java', 'C++', 'C']

item 1to-1 is: ['Swift', 'Python', 'Java', 'C++']

item 0-end is: ['Objective-c', 'Swift', 'Python', 'Java', 'C++', 'C']

new_item 7-end is: Language

item 0-4: sing

item 4to-4: le Lang

使用索引获取序列中各个项目，“[ ]”中指定序列的制定数组，Python 将返回该序列制定位置的项目，Python计数从0开始。索引计数也可以为负数，负数表示从序列的末尾向首位开始计数。

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还可以设置截取跨度长度

List[ : : 2]//表示从起始-结尾 截取长度为2的项目

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集合

代码实现

stu = set(['jone','tom','jerry','jack'])

print('stu:',stu)

print('jack is in stu? ','jack' in stu)

print('lee is in stu? ','lee' in stu)

stus = stu.copy()

stus.add('jodan')

print('stus:',stus)

print('stus is stu superset? ',stus.issuperset(stu))

print('stus and stu all item? ',stu | stus)

stus.remove('tom')

stus.add('robert')

print('stu:',stu)

print('stus:',stus)

print('stus and stu all item? ',stu | stus)

print('stus and stu intersection item? ',stu & stus)

输出结果

stu: {'jack', 'tom', 'jerry', 'jone'}

jack is in stu? True

lee is in stu? False

stus: {'tom', 'jack', 'jerry', 'jodan', 'jone'}

stus is stu superset? True

stus and stu all item? {'tom', 'jack', 'jerry', 'jodan', 'jone'}

stu: {'jack', 'tom', 'jerry', 'jone'}

stus: {'jack', 'robert', 'jerry', 'jodan', 'jone'}

stus and stu all item? {'tom', 'jack', 'robert', 'jerry', 'jodan', 'jone'}

stus and stu intersection item? {'jack', 'jerry', 'jone'}

set 支持拷贝、增加、删除等基本操作。

引用

创建一个对象，分配给该对象某个变量，变量只会 refer 某个对象，不会代表对象本身。变量名只是指向计算机内存储该对象的内存地址。在引用时候会出现不同的效果。

案例

List = ['Objective-c','Swift','Python','Java','C++','C']

new_list = List

# new_list 只是指向 List 地址的名称，List 改变，new_list也会随之改变

List.remove("C")

print('List:',List)

print('newList:',new_list)

# new_list 与 List 指向同一对象

copy_list = List[:]

# 通过切片 复制出一份 List 的副本

print('copy_list:',copy_list)

del copy_list[0]

print('List:',List)

print('newList:',new_list)

print('copy_list:',copy_list)

输出结果

List: ['Objective-c', 'Swift', 'Python', 'Java', 'C++']

newList: ['Objective-c', 'Swift', 'Python', 'Java', 'C++']

copy_list: ['Objective-c', 'Swift', 'Python', 'Java', 'C++']

List: ['Objective-c', 'Swift', 'Python', 'Java', 'C++']

newList: ['Objective-c', 'Swift', 'Python', 'Java', 'C++']

copy_list: ['Swift', 'Python', 'Java', 'C++']

如果想操作而又不影响源数据的情况下，使用 “ List[ : ] ” 这样得到的序列是拷贝出一份副本，互相操作不会影响；如果采用 “ a=b ”，则操作会造成联动，慎用！

字符串补充

代码实现

List = ['Objective-c','Swift','Python','Java','C++','C']

str = 'python'

if str.startswith('py'):

# 字符串以什么开头

print('str start at \'py\'')

if 'on' in str:

# 字符串包含

print('str contain \'on\'')

if str.find('th') != -1:

# 查找字符串的位置，如果找不到则返回"-1"

print('\'th\' in str location is:',str.find('th'))

otherStr = ' ~ '

print('List change str is:',otherStr.join(List))

#otherStr 是作为List 中每个项目的分隔符，返回一个更大的字符串

输出结果

str start at 'py'

str contain 'on'

'th' in str location is: 2

List change str is: Objective-c ~ Swift ~ Python ~ Java ~ C++ ~ C