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一些好用的函式或方法

一、zip
zip函式可以把兩個函式壓縮在一起,然後返回一個內含元組的列表。如果兩個序列不等長,當最短的序列用完時就會停止。
示例程式碼:

names = ['dnfag','anne','damon','Jhon','David']
ages = [20,25,30,35,40,45]
for name,age in zip(names,ages):
    print(f'{name} is {age} years old')

返回結果:
dnfag is 20 years old
anne is 25 years old
damon is 30 years old
Jhon is 35 years old
David is 40 years old

二、enumerate
enumerate函式可以獲取列表對應的索引和元素:
示例程式碼:

names = ['dnfag','anne','damon','Jhon','David']
for index,name in enumerate(names):
    print(index,name)

返回結果:
0 dnfag
1 anne
2 damon
3 Jhon
4 David
enumerate函式用於字典時也可以獲取到字典的key及對應的索引,而且是按原來的順序排列好的,如果想按字典的原順序讀取資料,這個還是有用處的:

names = {'dnfag':20,'anne':25,'damon':30,'Jhon':35,'David':40}
for index,name in enumerate(names):
    print(index,name)
    print(name,names[name])

返回結果:
0 dnfag
dnfag 20
1 anne
anne 25
2 damon
damon 30
3 Jhon
Jhon 35
4 David
David 40

三、isinstance
isinstance 用來判斷一個物件是否是一個已知的型別。函式返回值是布林值。若物件的型別是已知型別,那麼就返回True.否則返回False.用法:
isinstance(物件,物件型別)
物件型別有:int,float,bool,str,list,turple,set,dict
物件型別可以有多個,只要一個符合就返回True.如:

a = "abc"
isinstance(a,(int,str,float))

會返回True