005 python语法_002

Posted 2021-01-09 汁虫

 

 

 

/*
时间：2018/10/01
目录: 
　　一: list
          1 基本用法
　　二: 字典 
          1 语法1
          2 语法2
　　　　　　3 语法3
　　三: 集合
　　　　　　1 用法 - {}
　　　　　　2 用法 - set
　　　　　　3 集合运算
 */ 

 

一: list
　　1 基本用法

# coding:utf-8

list = []
print(list)
print(type(list))

nInt = 12
fFloat = 12.12
bTrue = True
bFalse = False
strString = "12.12"

# 尾部插入
list.append(nInt)
list.append(fFloat)
list.append(True)
list.append(False)
list.append(strString)
print(list)

# 指定插入
list.insert(1, "insert")    # 插入位置 - 索引为1
print(list)

# 删除尾部
list.pop()
print(list)

# 指定删除
list.pop(2)     # 删除位置 - 索引为1
print(list)

# 指定删除
del list[0]     # 删除位置 - 索引为0
print(list)

# 数据修改
list[0] = 22
print(list)

 

[]
<class \'list\'>
[12, 12.12, True, False, \'12.12\']
[12, \'insert\', 12.12, True, False, \'12.12\']
[12, \'insert\', 12.12, True, False]
[12, \'insert\', True, False]
[\'insert\', True, False]
[22, True, False]

 

二: 字典

1 字典可以嵌套字典
2 字典内容是无序的
3 字典key值是唯一的

 

　　1 语法1

# coding:utf-8

Dictionary = {
    1: 999999,
    12.12: "12.12",
    "a": "",
    "b": 123,
    "dict": {
        1: 123456,
        12.12: "12.12",
        "a": "",
        "b": 123,
        "test": {
            \'KK\': "mm",
            "jj": "nn"
        }
    }
}
print(Dictionary.keys())

# 查询
print(Dictionary[1])

print(Dictionary["dict"][1])
print(Dictionary["dict"]["test"]["KK"])

print(Dictionary)
print(Dictionary["b"])

# 增加内容
Dictionary["asd"] = "123456"
print(Dictionary)

# 修改内容
Dictionary[1] = "111111"        # 进行覆盖
print(Dictionary)

Dictionary["asd"] = "111111"    # 进行覆盖
print(Dictionary)

# 删除内容
del(Dictionary["dict"])
print(Dictionary)

print(Dictionary.keys())

dict_keys([1, 12.12, \'a\', \'b\', \'dict\'])
999999
123456
mm
{1: 999999, 12.12: \'12.12\', \'a\': \'\', \'b\': 123, \'dict\': {1: 123456, 12.12: \'12.12\', \'a\': \'\', \'b\': 123, \'test\': {\'KK\': \'mm\', \'jj\': \'nn\'}}}
123
{1: 999999, 12.12: \'12.12\', \'a\': \'\', \'b\': 123, \'dict\': {1: 123456, 12.12: \'12.12\', \'a\': \'\', \'b\': 123, \'test\': {\'KK\': \'mm\', \'jj\': \'nn\'}}, \'asd\': \'123456\'}
{1: \'111111\', 12.12: \'12.12\', \'a\': \'\', \'b\': 123, \'dict\': {1: 123456, 12.12: \'12.12\', \'a\': \'\', \'b\': 123, \'test\': {\'KK\': \'mm\', \'jj\': \'nn\'}}, \'asd\': \'123456\'}
{1: \'111111\', 12.12: \'12.12\', \'a\': \'\', \'b\': 123, \'dict\': {1: 123456, 12.12: \'12.12\', \'a\': \'\', \'b\': 123, \'test\': {\'KK\': \'mm\', \'jj\': \'nn\'}}, \'asd\': \'111111\'}
{1: \'111111\', 12.12: \'12.12\', \'a\': \'\', \'b\': 123, \'asd\': \'111111\'}
dict_keys([1, 12.12, \'a\', \'b\', \'asd\'])

 

　　2 语法2

# coding:utf-8

dicts = {"username":"zhangsan", "password":123456}
print(dicts.keys())
print(dicts.values())
print(dicts.items())

for key, value in dicts.items():
    print("%r is %r" %(key, value))

dict_keys([\'username\', \'password\'])
dict_values([\'zhangsan\', 123456])
dict_items([(\'username\', \'zhangsan\'), (\'password\', 123456)])
\'username\' is \'zhangsan\'
\'password\' is 123456

 　　

　　3 语法3

# coding:utf-8
nNum = 255
strNum = "123"
token = "xxxxxxx"
dict = {
    "nNum": nNum,
    "strNum": strNum,
    "strName": "My Name is %s, My age is %d" %(strNum, nNum),
    "list": [1, 2, nNum, 3],
    "token": token
}

print(dict)

{\'nNum\': 255, \'strNum\': \'123\', \'strName\': \'My Name is 123, My age is 255\', \'list\': [1, 2, 255, 3], \'token\': \'xxxxxxx\'}

 

三: 集合

1 集合是一个无序的不重复元素序列。
2 使用大括号{ }或者set()函数创建集合，
3 创建一个空集合必须用set()而不是{ }，因为{ }是用来创建一个空字典。

 

　　1 用法 - {}

# coding:utf-8
basket = {\'apple\', \'orange\', \'apple\', \'pear\', \'orange\', \'banana\'}

# 显示打印
print(basket)           # 显示集合 - 元素去重
print(len(basket))      # 显示个数 - 元素个数
print(type(basket))     # 显示类型 - basket

# 判断包含
print(\'orange\' in basket)   # 判断包含
print(\'abc\' in basket)      # 判断包含

print(\'abc\' not in basket)      # 判断不包含
print(\'orange\' not in basket)   # 判断不包含

# 增加元素
basket.add("kkk")
print(basket)

basket.update({"ZZZ"})
print(basket)

# 删除元素
basket.remove(\'apple\')
print(basket)

# Run Result
{\'orange\', \'banana\', \'pear\', \'apple\'}
4
<class \'set\'>
True
False
True
False
{\'orange\', \'kkk\', \'banana\', \'pear\', \'apple\'}
{\'orange\', \'kkk\', \'banana\', \'pear\', \'apple\', \'ZZZ\'}
{\'orange\', \'kkk\', \'banana\', \'pear\', \'ZZZ\'}

 

　　2 用法 - set

# coding:utf-8
thisSet = set(("google", "baidu", "bing"))
print(thisSet)            # 显示集合
print(type(thisSet))    # 显示类型
thisSet.add("Facebook")    # 增加元素
print(thisSet)            # 显示集合

# Run Result
{\'baidu\', \'google\', \'bing\'}
<class \'set\'>
{\'Facebook\', \'baidu\', \'google\', \'bing\'}

 

　　3 集合运算

# coding:utf-8
a = set(\'abracadabraK\')
b = set(\'alacazam\')
print(a)
print(type(a))
print(b)
print(type(b))

print(a - b)    # 显示元素 - b集合中不包含a集合
print(b - a)    # 显示元素 - a集合中不包含b集合

print(a | b)    # 显示元素 : a和b集合所有元素 - 不重复
print(a & b)    # 显示元素 - a和b集合都包含的元素
print(a ^ b)    # 显示元素 - 不同时包含于a和b的元素

# Run Result
{\'a\', \'d\', \'c\', \'K\', \'b\', \'r\'}
<class \'set\'>
{\'z\', \'m\', \'a\', \'l\', \'c\'}
<class \'set\'>
{\'K\', \'b\', \'r\', \'d\'}
{\'l\', \'z\', \'m\'}
{\'z\', \'m\', \'d\', \'a\', \'c\', \'K\', \'l\', \'b\', \'r\'}
{\'a\', \'c\'}
{\'K\', \'b\', \'z\', \'m\', \'l\', \'r\', \'d\'}