一、列表(list)
1.列表的格式
li = [11,22,"kobe",["lakers","ball",11],(11,22,),{"k1":11,"k2":"kuzma"},True,False]
2.列表可以嵌套任何格式,数字、字符串、列表、元组、字典、布尔值。
3.索引取值
li = [11,22,"kobe",["lakers","ball",11],(11,22,),{"k1":11,"k2":"kuzma"},True,False]
print(li[1])
4.切片取值
li = [11,22,"kobe",["lakers","ball",11],(11,22,),{"k1":11,"k2":"kuzma"},True,False]
print(li[1:-1])
5.for循环
li = [11, 22, "kobe", ["lakers", "ball", 11], (11, 22,), {"k1": 11, "k2": "kuzma"}, True, False]
for item in li:
print(item)
6.利用索引修改和删除
a.修改
li = [11, 22, "kobe", ["lakers", "ball", 11], (11, 22,), {"k1": 11, "k2": "kuzma"}, True, False]
li[2] = "randle"
print(li)
b.删除
li = [11, 22, "kobe", ["lakers", "ball", 11], (11, 22,), {"k1": 11, "k2": "kuzma"}, True, False]
del li[1]
print(li)
7.利用切片修改和删除
a.修改
li = [11, 22, "kobe", ["lakers", "ball", 11], (11, 22,), {"k1": 11, "k2": "kuzma"}, True, False]
li[0:2] = [33,44]
print(li)
b.删除
li = [11, 22, "kobe", ["lakers", "ball", 11], (11, 22,), {"k1": 11, "k2": "kuzma"}, True, False]
del li[0:4]
print(li)
8.in 操作
li = [11, 22, "kobe", ["lakers", "ball", 11], (11, 22,), {"k1": 11, "k2": "kuzma"}, True, False]
v ="ball" in li
print(v)
9.查找
li = [11, 22, "kobe", ["lakers", "ball", 11], (11, 22,), {"k1": 11, "k2": "kuzma"}, True, False]
v = li[3][2]
print(v)
10.转换
(1)字符串转列表
s = "hechouzi"
li = list(s)
print(li)
(2)列表转字符串
a.列表中有数字,要用for循环
li = [11, 22, "kobe", ["lakers", "ball", 11], (11, 22,), {"k1": 11, "k2": "kuzma"}, True, False]
s = ""
for item in li:
s = s + str(item)
print(type(s),s)
b.列表中只有字符串
li = ["123","hahah"]
v = "".join(li)
print(v)
11.方法
(1)append 原来值最后追加
li = [11, False, "kobe", ["lakers"], (11, 22,), {"k1": 11, "k2": "kuzma"}]
li.append(22)
print(li
(2)clear 清空列表
li = [11, False, "kobe", ["lakers"], (11, 22,), {"k1": 11, "k2": "kuzma"}]
li.clear()
print(li)
(3)copy (浅拷贝)
li = [11, False, "kobe", ["lakers"], (11, 22,), {"k1": 11, "k2": "kuzma"}]
v = li.copy()
print(v)
(4)count 计算元素出现的次数
li = [11, False,0, "kobe", ["lakers"], (11, 22,), {"k1": 11, "k2": "kuzma"}]
v = li.count(False)
print(v)
(5)extend 扩展原列表,参数:可迭代对象
li = [11, False,0, "kobe", ["lakers"], (11, 22,), {"k1": 11, "k2": "kuzma"}]
li.extend([(11,22),"33"])
print(li)
(6)index 根据值获取当前值的索引位置(左边优先)
li = [11, False,0, "kobe", ["lakers"], (11, 22,), {"k1": 11, "k2": "kuzma"}]
v = li.index(False)
print(v)
(7)insert 在指定索引位置插入元素
li = [11, False,0, "kobe", ["lakers"], (11, 22,), {"k1": 11, "k2": "kuzma"}]
li.insert(2,"randle")
print(li)
(8)pop(1:指定索引;2:默认删除最后一个) 删除某个值,并获取删除的值
li = [11, False,0, "kobe", ["lakers"], (11, 22,), {"k1": 11, "k2": "kuzma"}]
v = li.pop()
print(li,v)
(9)remove 删除列表中指定的值,左边优先
li = [11,22,33,33,44]
li.remove(33)
print(li)
(10)reverse 将列表进行翻转
li = [11,22,33,33,44]
li.reverse()
print(li)
(11)sort 排序
li = [11,22,33,33,44]
li.sort(reverse = True)
print(li)
二、元组(tuple)
1.元组的写法,一般在最后加,
tu = (11,"hehcouzi",)
2.元组的一级元素不可被修改,不能增加或删除
3.索引取值
tu = (11,"kobe",[22],{"key1":"ball"},)
v = tu [1]
print(v)
4.切片取值
tu = (11,"kobe",[22],{"key1":"ball"},)
v = tu [1:-1]
print(v)
5.for 循环
tu = (11, "kobe", [22], {"key1": "ball"},)
for item in tu:
print(item)
6.转换
s = "hehcouzi"
v1 = tuple(s)
v2 = list(v1)
print(v1,v2
三、字典(dict)
1.字典的基本结构
info = {“k1”:"v1","k2":"v2"}.key:value
2.字典的value可以是任何值
3.字典和列表不可做key值
4.字典是无序的
5.可以通过索引取值,不能切片
info = {"k1":11,"k2":"hechouzi","k3":("lakers"),1:22,True:11,}
v = info["k1"]
print(v)
6.del删除
info = {"k1":11,"k2":"hechouzi","k3":("lakers"),1:22,True:11,}
del info["k1"]
print(info)
7. for 循环,默认输出key值
a. info.items
输出key和value
info = {"k1":11,"k2":"hechouzi","k3":("lakers"),1:22,True:11,}
for item in info.items():
print(item)
b. info.values
输出value值
info = {"k1":11,"k2":"hechouzi","k3":("lakers"),1:22,True:11,}
for item in info.values():
print(item)
8.方法
(1)fromkeys
根据序列,创建字典,并赋予统一的值
v = dict.fromkeys(["k1","k2","k3"],"hahah")
print(v)
(2)get
a.寻找指定key值的value,找不到报错
info = {"k1":11,"k2":"hechouzi","k3":("lakers"),1:22,True:11,}
v =info["k1"]
print(v)
b.寻找指定key值的value,找不到返回指定值,默认为None
info = {"k1":11,"k2":"hechouzi","k3":("lakers"),1:22,True:11,}
v =info.get("k111",11111)
print(v)
(3) pop 删除并获取值
a.删除k1,并返回指定值
info = {"k1":11,"k2":"hechouzi","k3":("lakers"),1:22,True:11,}
v =info.pop("k1",11111)
print(info,v)
b.随机删除一个key和它对应的value
info = {"k1":11,"k2":"hechouzi","k3":("lakers"),1:22,True:11,}
k,v =info.popitem()
print(k,v,info)
(4)setdefault 设置值,已存在不设置并获取当前的value,不存在则设置并获取value
info = {"k1":11,"k2":"hechouzi","k3":("lakers"),1:22,True:11,}
v = info.setdefault("k1",123)
print(info,v)
(5) update 更新
两种方法
info = {"k1":11,"k2":"hechouzi","k3":("lakers"),1:22,True:11,}
# info.update({"k1":123,"k2":"hahaha"})
info.update(k1 = "lakers",k3=111,Ture=111)
print(info)
四、类的分类
1.根据是否可变分为
可变类型:列表、字典
不可变类型:字符串、数字、元组
2.根据访问顺序分为
直接访问:数字
顺序访问:字符串、列表、元组
映射访问:字典
3.存放元素个数
容器类型:列表、元组、字典
原子类型:数字、字符串