Better way to shuffle two related lists

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Is there better ways to randomly shuffle two related lists without breaking their correspondence in the other list? I've found related questions in numpy.array and c# but not exactly the same one.

As a first try, a simple zip trick will do:

import random
a = [[1, 2], [3, 4], [5, 6], [7, 8], [9, 10]]
b = [2, 4, 6, 8, 10]
c = zip(a, b)
random.shuffle(c)
a = [e[0] for e in c]
b = [e[1] for e in c]
print a
print b

It will get the output:

[[1, 2], [7, 8], [3, 4], [5, 6], [9, 10]]
[2, 8, 4, 6, 10]

Just find it a bit awkward. And it also need an additional list as well.

shuffle list python
8 Answers

You can do an unzip at the end to limit the awkwardness a bit?

import numpy as np
list1 = [1,2,3]
list2 = [4,5,7]
list_zipped = list(zip(list1,list2))
np.random.shuffle(list_zipped)
list1,list2 = zip(*z) #unzipping
user_44194260

Modified version of AlexConfused's approach which is more general and be copied and used directly:

from random import shuffle, getstate, setstate


def shuffle_inplace(lst, state):
    """ shuffle multiple lists in-place using order determined by state """
    setstate(state)
    shuffle(lst)


lst1 = [0, 1, 2, 3, 4]
lst2 = [5, 6, 7, 8, 9]

s = getstate()
shuffle_inplace(lst1, s)
shuffle_inplace(lst2, s)

print(lst1)
print(lst2)
user_60092800
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