元組
1.格式:
t=(元素,元素)
2.特點(diǎn):
有序惕味,可重復(fù)扇调,不可變榛了,任意類型
3.訪問元組
索引值存在:print(t[2])
索引值不存在:報(bào)錯
4.查詢:
1.查詢個數(shù):t.count(元素
2.查詢下標(biāo):t.index(元素)
5.修改:
不可修改在讶,虛轉(zhuǎn)換類型
6.類型轉(zhuǎn)換
1)列表轉(zhuǎn)換元祖
例如:
aa = [23,34,45,56,67]
a=tuple(aa)
print(a)
2)元組轉(zhuǎn)換列表
aTuple=('b','c','d','e','f','g')
a = list(aTuple)
print(a)
7.元組的循環(huán)取值
1)for循環(huán)
for i in aTuple:
? ? print(i)
2)while循環(huán)
?i=0
while i < len(aTuple):
? ? print(aTuple[i])
? ? i=i+1
字典
1.格式:
變量名={key1:value,key2:value,,,}
?列如:info={"name":"anfly","age":12,"sex":"男"}
2.根據(jù)key 訪問value:(3種)
1)? info={"name":"anfly","age":18,"sex":"男"}
? ? ?print(info["name"])
2)? info={"name":"anfly","age":12,"sex":"男"}
? ? ? print(info.get("name"))【沒有時返回None】
3)info={"name":"anfly","age":12,"sex":"男"}
? ? ? ?print(info.get("name12","無數(shù)據(jù)")) 【沒有時返回‘無數(shù)據(jù)’】
3.修改元素:
info={"name":"anfly","age":12,"sex":"男"}
info["age"]=14
print(info)
4.添加元素:
info={"name":"anfly","age":12,"sex":"男"}
info["gender"]="屬雞"
print(info)
總結(jié):有對應(yīng)的key則是修改數(shù)據(jù)煞抬,沒有對應(yīng)的key是新增數(shù)據(jù)
5.刪除元素:(2種)
del (刪除指定的元素)
1)? ?info={"name":"anfly","age":12,"sex":"男"}
? ? ? del info
? ? ? print(info) 【刪除完霜大,報(bào)錯顯示name 'info' is not defined】
2)? ? info={"name":"anfly","age":12,"sex":"男"}
? ? ? ? del info["name"]
? ? ? ? print(info) 【刪除某個元素】
clear清空
1)? ? ?info={"name":"anfly","age":12,"sex":"男"}
? ? ? ? info.clear()
? ? ? ? print(info)【刪除完,顯示{}】
6.查詢長度:
len():查詢鍵值對的個數(shù)
? ? ?info={"name":"anfly","age":12,"sex":"男"}
? ? ?print(len(info))
7.?字典中循環(huán):
取出字典中的key
info={"name":"anfly","age":12,"sex":"男"}
for i in info.keys():
print(i)
取出字典中的value
info={"name":"anfly","age":12,"sex":"男"}
for i in info.values():
print(i)
取出字典中的key和value
1)? info={"name":"anfly","age":12,"sex":"男"}
? ? ?for i in info.keys():
? ? ?print(i,info[i])
2)? info={"name":"anfly","age":12,"sex":"男"}
? ? ?for k,v in info.items():
? ? ?print(k,v)
enumerate()實(shí)現(xiàn)索引的遍歷
? ? names=["anfly","tom","Meachal"]
? ? for i,chr in enumerate(names):
? ? ?print(i,chr)
結(jié)果:0 anfly
? ? ? ? ? ?1 tom
? ? ? ? ? ?2 Meachal