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# str1 = "14356"
# str1 = list(str1)
# print(str1)
# list = ["中国",["湖北",["武汉"],"湖南"],"长沙"]
# print(list)
# print(list[1][1][0])
# list[2]="俄罗斯"
# print(list)

"""append 在列表中添加一个值"""
# list = ["中国",["湖北",["武汉"],"湖南"],"长沙"]
# list.append("江西")
# print(list)

"""extend 将b的内容追加在a的里面"""
# a = ["江西","武汉"]
# b = ["深圳","上海"]
# a.extend(b)
# print(a)

"""insert 插入值:-2是插入的索引位置,后面是插入值的内容"""
# a = ["江西","武汉"]
# a.insert(-2,"长沙")
# print(a)

"""remove 只能删除单个值,默认删除列表第一个匹配的值内容"""
# a = ["江西","武汉","南昌","深圳","南昌"]
# a.remove("南昌")
# a.remove(a[-1])
# print(a)

"""del 删除值,通过索引删除"""
# a = ["江西","武汉","南昌","深圳","南昌"]
# del a[1]
# print(a)

"""index 查询索引位置"""
# a = ["江西","武汉","南昌","深圳","南昌"]
# print(a.index("深圳"))

"""sort 列表内容排序,默认ascii码表排序"""
# a = ["江西","武汉","南昌","深圳","南昌"]
# a.sort()
# print(a)

"""reverse 反转输出"""
# a = ["江西","武汉","南昌","深圳","南昌"]
# a.reverse()
# print(a)
# print(a[::-1])

""" pop删除值单个,默认删除末尾值,可接索引位置"""
# a = ["江西","武汉","南昌","深圳","南昌"]
# a.pop(2)
# print(a)

"""
元组():tuple 是一个安全的数据类型,也是一个序列,里面内容无法更改
# 如果元组内只有一个值,那么他的数据类型为值属性,后面加上“,”变为tuple类型
# 更改tuple里面内容需要先将tuple转换为list,然后更改内容,最后再转换为tuple
"""
# tuple1 = (1,2,5,7,9)
# tuple2 = (1,)
# print(tuple1)
# print(type(tuple2))
# print(type(tuple1))
# print(tuple1[1:4])
# tuple1 = list(tuple1)
# print(tuple1)
# print(type(tuple1))
# del tuple1[2]
# print(tuple1)
# tuple1 = tuple(tuple1)
# print(type(tuple1))

"""
dict 字典存储数据的格式他是以 key 和 values 的形式
进行存储,他的键(key)是唯一的,values(值)不唯一
这种格式叫做键值队:前面是键(key),后面是值(values)
字典的表达式:{}
dict1= {"湖北":"武汉","湖南":"长沙"}
"""
# print(dict1)
# print(type(dict1))

"""
list不能转换为dict
dict可以转换为list,但是只会保留键
"""
# dict1= {"湖北":"武汉","湖南":"长沙"}
# dict1=list(dict1)
# print(dict1)
# print(type(dict1))

"""
dict可以转换为tuple,但是只会保留键
tuple无法转换为dict
"""
# dict1= {"湖北":"武汉","湖南":"长沙"}
# dict1=tuple(dict1)
# print(dict1)
# print(type(dict1))

"""
dict可以转换为str,str无法转换为str
"""
# dict1= {"湖北":"武汉","湖南":"长沙"}
# dict1=str(dict1)
# print(dict1)
# print(type(dict1))

"""
dict修改增加值:通过键对应值 dict["键名"]="数据值"
当前键不存在是增加,存在则是修改
"""
# dict1 = {"湖北":"武汉","湖南":"长沙"}
# dict1["安徽"]="安庆"
# print(dict1)
# dict1["湖南"]="浏阳"
# print(dict1)
"""通过键名取对应的值"""
# print(dict1["湖南"])
"""获取字典所有的值(values)"""
# print(dict1.values())
"""获取字典所有键值"""
# print(dict1.keys())
"""setdefsult:添加值:键存在是不会修改,键不存在则添加"""
# dict1.setdefault("四川","成都")
# print(dict1)

"""get取值:通过键取值"""
# dict1= {"湖北":"武汉","湖南":"长沙"}
# print(dict1.get("湖北"))

"""del 通过删除值"""
dict1= {"湖北":"武汉","湖南":"长沙"}
# del dict1["湖南"]
# print(dict1)
"""删除字典,慎用,会引发程序中断"""
# del dict1
# print(dict1)

"""clear清空字典内容"""
# dict1= {"湖北":"武汉","湖南":"长沙"}
# dict1.clear()
# print(dict1)

"""fromkeys 初始化一个字典:给不同的键,值只能给一个"""
# print({}.fromkeys(["湖北","湖南"],"武汉"))

"""update:将dict2字典内容追加在dict1内容中"""
# dict1= {"湖北":"武汉","湖南":"长沙"}
# dict2 ={"安徽":"安庆"}
# dict1.update(dict2)
# print(dict1)

"""items:同时获取字典的键值"""
# dict1= {"湖北":"武汉","湖南":"长沙"}
# print(dict1.items())

"""
__contains__ 判断语句:判断当前的键是否存在
python2的版本用has_key来判断
python3的版本用__contains__来判断
判断语句都是返回布尔值属性
"""
# dict1= {"湖北":"武汉","湖南":"长沙"}
# print(dict1.__contains__("键名"))
# print(dict1.__contains__("湖北"))

"""popitem:删除字典最后一个键值"""
# dict1= {"湖北":"武汉","湖南":"长沙","江西":"南昌"}
# dict1.popitem()
# print(dict1)

"""pop 删除指定键值   dict1.pop("键名")"""
# dict1= {"湖北":"武汉","湖南":"长沙","江西":"南昌"}
# dict1.pop("湖北")
# print(dict1)

"""
数据类型:集合:{}
可变集合:set  里面的内容可以进行操作
不可变集合:frozenset 里面的内容不能进行操作
"""
# set1={1,2,3,4,5,5,4,3,2,1}
# print(type(set1))
"""集合可以用来数据去重:"""
# set1={1,2,3,4,5,5,4,3,2,1}
# print(set1)
"""添加内容"""
# set1.add(345)
# print(set1)
"""删除内容"""
# set1.remove(2)
# print(set1)
"""改数据集合类型"""
# set1=frozenset(set1)
# print(type(set1))
# print(set1)

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