- dict
- '''
- # 数据类型划分: 可变数据类型, 不可变数据类型
- 不可变数据类型: 元组, bool int str 可哈希
- 可变数据类型: list,dict set 不可哈希
- dict key 必须是不可变数据类型, 可哈希,
- value: 任意数据类型.
- dict 优点: 二分查找去查询
- 存储大量的关系型数据
- 特点: 无序的
- '''
- # dic = {
- # 'name':['大猛','小孟'],
- # 'py9':[{'num':71,'avg_age':18,},
- # {'num': 71, 'avg_age': 18, },
- # {'num': 71, 'avg_age': 18, },
- # ],
- # True:1,
- # (1,2,3):'wuyiyi',
- # 2:'二哥',
- # }
- # print(dic)
- dic1 = {'age': 18, 'name': 'jin', 'sex': 'male',}
- # 增:
- # dic1['high'] = 185 #没有键值对, 添加
- # dic1['age'] = 16 #如果有键, 则值覆盖
- # dic1.setdefault('weight') # 有键值对, 不做任何改变, 没有才添加.
- # dic1.setdefault('weight',150)
- # dic1.setdefault('name','二哥')
- # print(dic1)
- # 删
- # print(dic1.pop('age')) # 有返回值, 按键去删除
- # print(dic1.pop('二哥',None)) # 可设置返回值
- # print(dic1)
- # print(dic1.popitem()) # 随机删除 有返回值 元组里面是删除的键值.
- # # print(dic1)
- # del dic1['name1']
- # print(dic1)
- # del dic1
- # print(dic1)
- # dic1.clear() #清空字典
- # 改 update
- # dic1['age'] = 16
- # dic = {"name":"jin","age":18,"sex":"male"}
- # dic2 = {"name":"alex","weight":75}
- # dic2.update(dic) #
- #
- # print(dic)
- # print(dic2)
- dic1 = {'age': 18, 'name': 'jin', 'sex': 'male',}
- # 查
- # print(dic1.keys(),type(dic1.keys()))
- # print(dic1.values())
- # print(dic1.items())
- # for i in dic1:
- # print(i)
- # for i in dic1.keys():
- # print(i)
- # for i in dic1.values():
- # print(i)
- # a,b = 1,2
- # print(a,b)
- # a = 1
- # b = 2
- # a,b = b,a
- # print(a,b)
- # a,b = [1,2],[2,3]
- # a,b = (1,2)
- # print(a,b)
- # for k,v in dic1.items():
- # print(k,v)
- # v1 = dic1['name']
- # print(v1)
- # v2 = dic1['name1'] # 报错
- # print(v2)
- # print(dic1.get('name1','没有这个键'))
来源: http://www.bubuko.com/infodetail-3046117.html