的一、列表
append(末尾添加):
代码:
li = [12,22,33,"44","65"] li.append(5) print(li) 结果:[12, 22, 33, '44', '65', 5]
clear(清空):
代码:
li = [12,22,33,"44","65"] li.clear() print(li) 结果:[]
copy(拷贝,浅拷贝):
代码:
li = [12,22,33,"44","65"] v = li.copy() print(li) print(v) 结果:[12, 22, 33, '44', '65'] [12, 22, 33, '44', '65']
count(计算出现次数):
代码:
li = [12,22,33,"44","65"] v = li.count(22) print(v) 结果:1
extend(扩展了原列表):
代码:
li = [12,22,33,"44","65"] li.extend([666,"aiankg"]) print(li) 结果:[12, 22, 33, '44', '65', 666, 'aiankg']
index(获取索引):
代码:
li = [12,22,33,"44","65"] v = li.index(33) print(v) 结果:2
insert(根据索引插入元素):
代码:
li = [12,22,33,"44","65"] li.insert(2,"insert") print(li) 结果:[12, 22, 'insert', 33, '44', '65']
pop(删除):默认最后一个删除,也可以指定索引
代码:
li = [12,22,33,"44","65"] li.pop() print(li) 结果:[12, 22, 33, '44']
li = [12,22,33,"44","65"] li.pop(2) print(li) 结果:[12, 22, '44', '65']
remove(指定删除元素):
代码:
li = [12,22,33,"44","65"] li.remove(33) print(li) 结果:[12, 22, '44', '65']
reverse(反转):
代码:
li = [12,22,33,"44","65"] li.reverse() print(li) 结果:['65', '44', 33, 22, 12]
sort(从小到大排序):
代码:
li = [55,22,48,96,84,6,10] li.sort() print(li) 结果:[6, 10, 22, 48, 55, 84, 96]
二、元组(末尾加,)
元组形式:tu = (10,“55”,[12,"aiakng"],[(18)],)
元组中列表只属于一个元素
count(获取元素出现次数):
代码:
tu = (10,"55",[12,"aikang"],[(18)],) v = tu.count(10) print(v) 结果:1
index(索引):
代码:
tu = (10,"55",[12,"aikang"],[(18)],) v = tu.index("55") print(v) 结果:1
三、字典
字典结构:
键值对
info = {"k1":123,2:"234","3":["aikang"]}
列表不能最作为字典的key,布尔值可以作为key使用要注意值和数字key重复,字典是无序列的,支持删除,支持for循环
items(获取键值对):用列表输出。
代码:
info = {"k1":123,2:"234","3":["aikang"]} v = info.items() print(v) 结果:dict_items([('k1', 123), (2, '234'), ('3', ['aikang'])])
info = {"k1":123,2:"234","3":["aikang"]} for k ,v in info.items(): print(k,v) 结果: k1 123 2 234 3 ['aikang']
fromkeys(根据序列创建字典,并用统一值赋值):
代码:
info = {"k1":123,2:"234","3":["aikang"]} v = info.fromkeys(["4",5,"hui"],987) print(info) print(v) 结果:{'k1': 123, 2: '234', '3': ['aikang']} {'4': 987, 5: 987, 'hui': 987}
get(根据key获取值,如果不存在输出None)
代码:
info = {"k1":123,2:"234","3":["aikang"]} v = info.get("k1") print(v) i = info.get("k8") print(i) 结果:123 None
pop(删除key指定,如果不存在输出指定值)
代码:
info = {"k1":123,2:"234","3":["aikang"]} v = info.pop("k1",90) print(v) print(info) 结果: 123 {2: '234', '3': ['aikang']}
popitem(随机返回并删除字典中的一对键和值):
代码;
info = {"k1":123,2:"234","3":["aikang"]} v = info.popitem() print(v) print(info) 结果:('3', ['aikang']) {'k1': 123, 2: '234'}
setdefault(设置值):
说明:
已存在值,不设置,获取当前key对应的值,
不存在值,设置值,获取当前key对应的值
代码:
info = {"k1":123,2:"234","3":["aikang"]} v = info.setdefault("k1","love") print(info) print(v) 结果:{'k1': 123, 2: '234', '3': ['aikang']} 123 i = info.setdefault("k5","love") print(info) print(i) 结果:{'k1': 123, 2: '234', '3': ['aikang'], 'k5': 'love'} love
update(跟新):
记得大括号
代码:
info = {"k1":123,2:"234","3":["aikang"]} info.update({"k1":258}) print(info) 结果:{'k1': 258, 2: '234', '3': ['aikang']}
keys() values() items() get update 最重要