Random double loop in Python

Question

I would like to create a random double loop in Python.

For example, for (N,N)=(2,2) the program should give:

Or another example

So far, I have done this:

r1 = list(range(2))
r2 = list(range(2))
random.shuffle(r1)
random.shuffle(r2)
for i in r1:
    for j in r2:
        # Do something with i

This, however, does not give the desired result, because I want i's to be shuffled too and not give for example all (1,x) sequentially. Any ideas?

chepner · Accepted Answer · 2019-11-22 18:38:53Z

5

Shuffle the product of the ranges, not each individual range.

import itertools


pairs = list(itertools.product(r1, r2))  # [(i,j) for i in r1 for j in r2]
random.shuffle(pairs)

for i, j in pairs:
    ...

answered Nov 22, 2019 at 18:38

chepner

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