Analysis of Slicing and Copying Examples of python List

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Slicing, that is, processing part of the data in a complete list.

Syntax Variable [Start Index: End Index: Step Size]

First create a list of 1 strings

>>> cars = ['toyota', 'honda', 'mazda', 'nissan', 'mitsubishi', 'subaru', 'suzuki', 'isuzu']
>>> 
>>> cars
['toyota', 'honda', 'mazda', 'nissan', 'mitsubishi', 'subaru', 'suzuki', 'isuzu']

View only the first 3 elements of the list

>>> print(cars[0:3])
['toyota', 'honda', 'mazda']

You can also not specify the starting index bit, which starts from 0 by default

>>> print(cars[:3])
['toyota', 'honda', 'mazda']

View elements 3 through 5 of the list

>>> print(cars[2:6])
['mazda', 'nissan', 'mitsubishi', 'subaru']

View the value from the third to the end of the list, do not specify the termination index bit, and default to the end of the list

>>> print(cars[2:])
['mazda', 'nissan', 'mitsubishi', 'subaru', 'suzuki', 'isuzu']

From the above two examples, we can see that slicing follows the principle of "wrapping header without wrapping tail",

Print all values of the list with step size 2

>>> print(cars[::2])
['toyota', 'mazda', 'mitsubishi', 'suzuki']

Copy 1 copy of cars list data to vivi list

>>> vivi = cars[:]
>>> 
>>> vivi
['toyota', 'honda', 'mazda', 'nissan', 'mitsubishi', 'subaru', 'suzuki', 'isuzu']
>>> 
>>> del cars
>>> 
>>> vivi
['toyota', 'honda', 'mazda', 'nissan', 'mitsubishi', 'subaru', 'suzuki', 'isuzu']