Create array from randomly extracted data from array of arrays-CodePudding

Suppose that I have the following array or arrays:

[[0, 1, 2, 3, 4, 5, 6, 7, 8, 9],[0, 1, 2, 3, 4, 5],[0, 1, 2, 3, 4, 5, 6, 7]]

What's the best way to loop into the main array and randomly extract one number from each sub-array every time and create another array with them? For instance, in the first pass, the result would be:

[2,5,6]

The second pass could be:

[8,0,7]

etc. At this stage I don't have any clues how to do it.

CodePudding user response：

If you have python lists, you can use random.choice in a list comprehension:

L = [[0, 1, 2, 3, 4, 5, 6, 7, 8, 9],[0, 1, 2, 3, 4, 5],[0, 1, 2, 3, 4, 5, 6, 7]]

from random import choice

out = [choice(l) for l in L]

example output:

[3, 0, 5]

variant

Imagine you want to pick each item only a single time in each iteration, you could also use pop on a random position:

L = [[0, 1, 2, 3, 4, 5, 6, 7, 8, 9],[0, 1, 2, 3, 4, 5],[0, 1, 2, 3, 4, 5, 6, 7]]

for i in range(6):
    print([l.pop(np.random.randint(len(l))) for l in L])

Obviously, here you cannot have a number of iterations greater than the length of the shortest sublist

example output:

[5, 4, 0]
[2, 2, 6]
[3, 5, 7]
[0, 1, 1]
[4, 3, 2]
[9, 0, 3]