Python creates an empty list and explains the usage of append

This article mainly introduces how to create an empty list in Python and how to use append. It has certain reference value. Now I share it with you. Friends in need can refer to it

Usage of list in Python : How to create a list, how to express elements in the list, how to modify and delete the list

Running environment: Python 3.6.2

0. Creation of an empty list:

l = list()

Or:

l = []

1.Creation and expression of elements in list

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fruits = ['apple', 'banana', 'pear', 'grapes', 'pineapple', 'watermelon']
fruits[2] #从0开始数起，第三个元素
pear

2.Change of elements in list

fruits[2] = 'tomato'
print(fruits)
['apple', 'banana', 'tomato', 'grapes', 'pineapple', 'watermelon']

3. Add more elements to the end of the list

fruits.append('eggplant')
print(fruits)
['apple', 'banana', 'tomato', 'grapes', 'pineapple', 'watermelon', 'eggplant']

4. How to intercept a certain paragraph in the list

print(fruit[: 2]) #从list的首元素开始截取，截取到位置'3'，但不包括第3个元素
['apple', 'banana']

5. How to change consecutive elements in the list

fruits[:2] = ['a', 'b']
print(fruits)
['a', 'b', 'tomato', 'grapes', 'pineapple', 'watermelon', 'eggplant']

6 .How to delete a certain element in the list, or the entire list

fruits[:2] = [] #删除前两个元素
print(fruits)
['tomato', 'grapes', 'pineapple', 'watermelon', 'eggplant']
fruits[:] = [] #删除全部list元素
[]

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Python implementation method of creating a list and adding elements to the list_python

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