shuffle a nested list

[deanhystad]

random.shuffle() is a function that only produces a side effect. The items in the provided list are shuffled. random.shuffle() does not create a list. random.shuffle does not return a list (it returns None).

If you want to use random.shuffle you need to first create you list of lists, then you can shuffle each list.

import random

def randomlist(values, count):
    retval = [values for _ in range(count)]
    for values in retval:
        random.shuffle(values)
    return retval

print(randomlist([1,2,3], 8))

random.sample can be used to create a shuffled list. Unlike shuffle() it creates a new list. This allows creating the lists and shuffling in a single step.

def randomlist(values, count):
    return [random.sample(values, k=len(values)) for _ in range(count)]

[perfringo]

Ohh i got it thank you very much.But is there a way to do what i want to do?

Actually I don't know what you want to do .

But maybe you want something along those lines:

>>> nums = list(range(5))
>>> [random.sample(nums, len(nums)) for i in range(5)]
[[0, 3, 4, 2, 1],
 [2, 1, 0, 4, 3],
 [3, 0, 4, 2, 1],
 [2, 3, 1, 0, 4],
 [3, 0, 1, 2, 4]]