Python: List Operations Summary

One, create a list

Just enclose the comma-delimited data items in square brackets.

1 list1=['physics','chemistry', 1997,2000]  2 list2=[1,2,3,4,5,6,7]

[Note]: 1. Data items in the list do not need to have the same data type

2. The index of the list starts at 0, and the list can be intercepted, combined

Second, access the value in the list

Use the subscript index to access the values in the list, and you can also use square brackets to intercept the characters

1list1=['Physics','Chemistry', 1997,2000]2list2=[1,2,3,4,5,6,7]3 4 Print('List1[0]:', List1[0])#output: list1[0]:p hysics5 Print('List2[1:5]:', List2[1:5])#output: [2,3,4,5]

Third, List script operators

P Ython-expression	Results	Describe
Len ([+])	3	Length
[1,2,3]+[4,5,6]	[1,2,3,4,5,6]	Combination
[' hi! '] *	[' hi! ', ' hi! ', ' hi! ', ' hi! ']	Repeat
3 in [All in all]	True	Whether the element exists in the list
For x in [All-in-A-Z]: print (x)	The	Iteration

Iv. List interception

The hypothetical list is as follows:

list=[1,2,3,4,5,6,7,8,9]

Operation:

Python expressions	Results	Describe
LIST[2]	3	Read the third element in the list
List[-2]	8	Reads the second-to-last element in a list
List[1:4]	[2,3,4]	Intercepting an element from subscript 1 to subscript 4 (excluding elements of subscript 4), the result is a list
List[1:8:2]	[2,4,6,8]	Intercept elements starting from subscript 1 to subscript 8 (excluding elements of subscript 8), step 2, and result as a list
List[:3]	[A]	An element that is truncated from the first element of the list to the subscript 3 (excluding the element with subscript 3), resulting in a list
List[5:]	[6,7,8,9]	Intercepts an element from subscript 5 to the end of the list, and the result is a list
list[:]	[1,2,3,4,5,6,7,8,9]	Copy the entire list

Python: List Operations Summary