python list slice usage

First, a list of sliced ​​very basic, must remember the simplicity!

= test_list [1,2,3,4,5,6 ] 

# start with an index to index 2. 5 
Print (test_list [2:. 5 ])
 # start to the end of the index 3 from the 
Print (test_list [3 :])
 # from the beginning to the index position 5 
Print (test_list [: 5 ])
 # from the beginning to the end of the 
Print (test_list [:])
 # cyclic list print data 
for Item in test_list:
     Print (Item)

The results are:

 

[3, 4, 5]
[4, 5, 6]
[1, 2, 3, 4, 5]
[1, 2, 3, 4, 5, 6]
1
2
3
4
5
6

Under standard list [] is left to follow the package does not include the right principle, the subscript starts at 0

Second, the string may be sliced

= STR " People's Republic of China " 
Print (STR [. 1:. 5: 2 ])
 # start with an index to index 2. 5 
Print (STR [2:. 5 ])
 # start to the end of the subscript 3 
Print (STR [3 :])
 # from the beginning to the index position 5 
Print (STR [: 5])

The results are:

China and China
People's Republic of
China Republic
of China People's Republic

Wherein str [1: 5: 2], in brackets, is a first start position (including), a second end position (not included), a third interval value, that is, in the front range, every few take a value, the list also have this usage, the default is 1, this value is omitted if not written, then the final colon may be omitted

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Origin www.cnblogs.com/cys52/p/12619424.html