python 列表、元组、字典，,python 列表、

python 列表、元组、字典，,python 列表、

python 列表、元组、字典

1、python 变理赋值

2、ptython 列表

3、python 元组

4、python 字典

1、 Python变量赋值

1.1变量的命名规则

变量名只能是 字母、数字或下划线的任意组合

变量名的第一个字符不能是数字

以下关键字不能声明为变量名

[‘assert‘，‘and‘, ‘as‘, ‘break‘, ‘class‘, ‘continue‘, ‘def‘, ‘del‘, ‘elif‘, ‘else‘, ‘except‘, ‘exec‘, ‘finally‘, ‘for‘, ‘from‘, ‘global‘, ‘if‘, ‘import‘, ‘in‘, ‘is‘, ‘lambda‘, ‘not‘, ‘or‘, ‘pass‘, ‘print‘, ‘raise‘, ‘return‘, ‘try‘, ‘while‘, ‘with‘, ‘yield‘]

1.2变量赋值的三种方式

传统赋值:student = “kezi”

链式赋值:student= user = “kezi”

序列解包赋值:stuent,age = “kezi”，10

>>> student="kezi">>> print(student)kezi>>> student2=student>>> print(student2)kezi>>> student="keke">>> print (student2)kezi>>> print(student)keke

2、 python列表

列表是我们最常用的数据类型之一,是一个元素以逗号分割，以中括号包围的,有序的，可修改、存储、的序列。

例子：

>>> student=["zhangshan","liuliu","taotao","junjun","xixi"]>>> student[1:4][‘liuliu‘, ‘taotao‘, ‘junjun‘]>>> student[2:-1][‘taotao‘, ‘junjun‘]>>> student[2:-1][‘taotao‘, ‘junjun‘]>>> student[2:][‘taotao‘, ‘junjun‘, ‘xixi‘]>>> student[0:2:][‘zhangshan‘, ‘liuliu‘]>>> 

2.2列表的方法

例子：

列表的添加

>>> student[‘zhangshan‘, ‘liuliu‘, ‘taotao‘, ‘junjun‘, ‘xixi‘]>>> student.insert(2,"honghonghong")   #默认是从下标是0开始的，0，1，2，3，4，，，，>>> student[‘zhangshan‘, ‘liuliu‘, ‘honghonghong‘, ‘taotao‘, ‘junjun‘, ‘xixi‘]
>>> student[‘zhangshan‘, ‘liuliu‘, ‘honghonghong‘, ‘taotao‘, ‘junjun‘, ‘xixi‘]>>> student.append("haihaihai")>>> student[‘zhangshan‘, ‘liuliu‘, ‘honghonghong‘, ‘taotao‘, ‘junjun‘, ‘xixi‘, ‘haihaihai‘]>>> student.extend("kaikaikai")>>> student[‘zhangshan‘, ‘liuliu‘, ‘honghonghong‘, ‘taotao‘, ‘junjun‘, ‘xixi‘, ‘haihaihai‘, ‘k‘, ‘a‘, ‘i‘, ‘k‘, ‘a‘, ‘i‘, ‘k‘, ‘a‘, ‘i‘]

统计

>>> student[‘zhangshan‘, ‘liuliu‘, ‘honghonghong‘, ‘taotao‘, ‘junjun‘, ‘xixi‘, ‘haihaihai‘, ‘k‘, ‘a‘, ‘i‘, ‘k‘, ‘a‘, ‘i‘, ‘k‘, ‘a‘, ‘i‘]>>> student.count("k")3

删除

>>> student.remove("k")>>> student[‘zhangshan‘, ‘liuliu‘, ‘honghonghong‘, ‘taotao‘, ‘junjun‘, ‘xixi‘, ‘haihaihai‘, ‘a‘, ‘i‘, ‘k‘, ‘a‘, ‘i‘, ‘k‘, ‘a‘, ‘i‘]>>> student.pop()‘i‘>>> student[‘zhangshan‘, ‘liuliu‘, ‘honghonghong‘, ‘taotao‘, ‘junjun‘, ‘xixi‘, ‘haihaihai‘, ‘a‘, ‘i‘, ‘k‘, ‘a‘, ‘i‘, ‘k‘, ‘a‘]>>> del student[8]>>> student[‘zhangshan‘, ‘liuliu‘, ‘honghonghong‘, ‘taotao‘, ‘junjun‘, ‘xixi‘, ‘haihaihai‘, ‘a‘, ‘k‘, ‘a‘, ‘i‘, ‘k‘, ‘a‘]

python 列表、元组、字典