Python multi-dimensional array initialization code

Source: Internet
Author: User
Python multi-dimensional array method example code initialize an array of 5x3 and each item is 0 in Python. the best method is:
Multilist = [[0 For Col In Range ( 5 )] For Row In Range ( 3 )]
We know that to initialize a one-dimensional array, we can do this:
Alist = [0] * 5
Yes, can we do this when initializing a two-dimensional array:
Multi = [[0] * 5 ] * 3
In fact, this is not correct, because [0] * 5 is an object in a one-dimensional array, and * 3 only copies the object reference three times. for example, modify multi [0] [0]:
Multi = [[0] * 5 ] * 3
Multi [0] [0] = ' Love China '
Print MultiThe output result is:
[['Love China', 0, 0, 0, 0], ['Love China', 0, 0, 0], ['Love China', 0, 0, 0, 0]
We modified multi [0] [0], but modified our multi [1] [0] and multi [2] [0. This is not the expected result.

If we write it like this:
Multilist = [[0] * 5 For Row In Range ( 3 )]
Multilist [0] [0] = ' Love China '
Print MultilistThe output result is as follows:
[['Love China', 0, 0, 0, 0], [0, 0, 0, 0, 0], [0, 0, 0, 0, 0]
Well, no problem. However, because the * method is easy to cause confusion and causes bugs, we recommend that you use the first method, namely:
Multilist = [[0 For Col In Range ( 5 )] For Row In Range ( 3 )]

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