Shulou(Shulou.com)06/02 Report--

In this issue, the editor will bring you the operational analysis of the practical application of the data structure in the Python array. The article is rich in content and analyzed and described from a professional point of view. I hope you can get something after reading this article.

The Python list is not covered in detail in this article, but you can refer to the Python documentation. There is no array data structure in the Python array, but the list is very much like an array, such as:

A = [0BZ 1 Jol 2]

At this time

A [0] = 0, a [1] = 1, a [2] = 2

But it leads to a question, that is, what if the array a wants to be defined as 0 to 999, which may be achieved by a = range (0, 1000). Or omit a = range (1000). If you want to define an of 1000 length, and the initial values are all 0, then

A = [0 for x in range (0, 1000)]

The following is the definition of a two-dimensional array: direct definition

A = [[1jue 1], [1JI]]

A two-dimensional array of 2'2 with an initial value of 0 is defined here. Indirect definition

A = [[0 for x in range (10)] for y in range (10)]

Here the Python array defines a two-dimensional array with an initial value of 0 from 10 to 10. Later, I found a simpler two-dimensional array of words on the Internet:

B = [[0] * 10] * 10

Defines a two-dimensional array of 10: 10 with an initial value of 0. Vs.

A = [[0 for x in range (10)] for y in range (10)]

Comparison: the result of print astatb is True. However, after using the definition method of b instead of a, the previous programs that can run normally also went wrong. after careful analysis, we can draw the difference: a [0] [0] = 1, only a [0] [0] is 1, and the others are all 0. B [0] [0] = 1, a [0] [0], a [1] [0], until a [9] is all 1. As a result, the 10 small one-dimensional data in the large array are all the same reference, that is, pointing to the same address. Therefore, b = [[0] * 10] * 10 does not conform to our conventional two-dimensional array.

At the same time, it has been tested that the definition of c = [0] * 10 has the same effect as that of c = [0 for x in range (10)]. The problem of Python array without the same reference above is that the definition of array c is multiplied by the value type, while the previous b is multiplied by the type, because the one-dimensional array is a reference.

The above is the operation analysis of the practical data structure in the Python array shared by the editor. If you happen to have similar doubts, you might as well refer to the above analysis to understand. If you want to know more about it, you are welcome to follow the industry information channel.

Welcome to subscribe "Shulou Technology Information " to get latest news, interesting things and hot topics in the IT industry, and controls the hottest and latest Internet news, technology news and IT industry trends.