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This article mainly introduces how to use negative index in python. It is very detailed and has certain reference value. Friends who are interested must finish reading it.

Negative index

People like to use sequences because when we know the order of elements, we can manipulate them in order. Strings, tuples, and lists are the most common sequence data types in Python. We can use the index to access individual items. Like other major programming languages, Python supports 0-based indexes, in which we use zeros to access the first element in square brackets. In addition, we can use slice objects to retrieve specific elements of the sequence, as shown in the following code example.

> > # Positive Indexing... Numbers = [1,2,3,4,5,6,7,8]. Print ("First Number:", numbers [0]). Print ("First Four Numbers:", numbers [: 4]). Print ("Odd Numbers:", numbers [:: 2]). First Number: 1 First Four Numbers: [1, 2, 3, 4] Odd Numbers: [1, 3, 5, 7]

However, Python goes a step further by supporting negative indexes. Specifically, we can use-1 to refer to the last element in the sequence and count backwards. For example, the index of the last element is-2, and so on. Importantly, negative indexes can also be used with positive indexes in sliced objects.

> > # Negative Indexing... Data_shape = (100,50,4). Names = ["John", "Aaron", "Mike", "Danny"]. Hello = "Hello World!". Print (data_shape [- 1])... Print (names [- 3 muri 1]). Print (Helo [1:-1:2]). 4 ['Aaron',' Mike'] el ol is all the content of the article "how python uses negative Index". Thank you for reading! Hope to share the content to help you, more related knowledge, welcome to follow the industry information channel!

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