python基礎-list

1、list建立

new_list1 = ['TV','Car','Cloth','Food']
new_list2 = list(['TV','Car','Cloth','Food'])
print (new_list1)
print (new_list2)
運行結果:
['TV', 'Car', 'Cloth', 'Food']
['TV', 'Car', 'Cloth', 'Food']

2、list常用的方法:

1. append

new_list1 = ['TV','Car','Cloth','Food']
print (new_list1)
new_list1.append('Water') #追加'water'
print (new_list1)
運行結果:
['TV', 'Car', 'Cloth', 'Food']
['TV', 'Car', 'Cloth', 'Food', 'Water']

2.count

new_list1 = ['TV','Car','Cloth','Food','Food']
print (new_list1.count('Food')) #統計'food'在列表中的次數 => 2次

3.extend

new_list1 = ['TV','Car','Cloth','Food','Food']
new_list1.extend([11,22,33,'Car'])
print (new_list1)
運行結果:
['TV', 'Car', 'Cloth', 'Food', 'Food', 11, 22, 33, 'Car']

4.sort

new_list1 = ['TV','Car','Cloth','Food','Food']
print (new_list1)
new_list1.sort()#正向排序
print (new_list1)
new_list1.sort(reverse=True)#反向排序
print (new_list1)
運行結果:
['TV', 'Car', 'Cloth', 'Food', 'Food']
['Car', 'Cloth', 'Food', 'Food', 'TV']#正向排序結果
['TV', 'Food', 'Food', 'Cloth', 'Car']#反向排序結果

5. len

new_list1 = ['TV','Car','Food','Cloth','Food']
print (len(new_list1)) => 5 #列印元素的個數

6.remove

new_list1 = ['TV','Car','Food','Cloth','Food']

new_list1.remove('Food')
print (new_list1)
運行結果:
['TV', 'Car', 'Cloth', 'Food'] #remove會刪除找到的第一個相同元素

7.pop

new_list1 = ['TV','Car','Food','Cloth','Food']
new_list1.pop()#隨機刪除一個元素
print (new_list1)
new_list1.pop(2)#指定刪除某個元素
print (new_list1)
運行結果為:
['TV', 'Car', 'Food', 'Cloth']
['TV', 'Car', 'Cloth']#,此處刪除的是第3個元素'Food'

8.index

new_list1 = ['TV','Car','Food','Cloth','Food']
print (new_list1.index('Food'))#返回指定元素的index值，相同元素返回尋找到的第一個
運行結果為:2

9.insert

new_list1 = ['TV','Car','Food','Cloth','Food']
new_list1.insert(2,'HAHAHA') #向指定的位置插入元素
print (new_list1)
運行結果為:
['TV', 'Car', 'HAHAHA', 'Food', 'Cloth', 'Food']

