How to check in Python if one tuple is an exact, ordered subsequence of the other?

Question

I have a list of tuples of various lengths and need to find a method to check if there are tuples that are an exact, ordered subsequence of one another. I will show with an example what I mean in this context:

Assume I have the following tuples:

t1 = (37, 5, 3, 22, 1)
t2 = (3, 5, 22)
t3 = (3, 22, 1)
t4 = (37, 41, 19)

Let's call the hypothetical function check_sub_tuple. Then the function should give the following outputs:

check_sub_tuple(t1, t2) = False, (t2 is not a subtuple of t1)
check_sub_tuple(t1, t3) = True, (t3 is a subtuple of t1)
check_sub_tuple(ti, tj) = False for all other pairs of tuples ti and tj in the example

Question 1: Is there existing Python functionality for this? I know I could do this:

set(my_tuple_2).issubset(my_tuple_1)

But this just checks if the elements of one tuple are contained in the other, I also need the order to be the same.

Question 2: How can I do the exact same thing for lists instead of tuples?

So your input is a list of lists/tuples? What about the exact output in the example then? Just to confirm. — Daniel Hao, May 19 '21 at 21:55
@Daniel Hao True, I either have a list with only lists or a list with only tuples, and I need to check which pairs of lists/tuples are subsequences of another — Peter, May 19 '21 at 22:00
In case tuples consist of integers in `range(0, 256)`, you can use `bytes(ti) in bytes(tj)`. — hilberts_drinking_problem, May 19 '21 at 22:01

score 0 · Answer 1 · answered May 19 '21 at 21:59

0

I think you could use this:

t1 = [37, 5, 3, 22, 1]
t2 = [3, 22, 1]

any(t2 == t1[i:i+len(t2)] for i in range(0,len(t1)))

answered May 19 '21 at 21:59

CAIO WANDERLEY

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How to check in Python if one tuple is an exact, ordered subsequence of the other?

1 Answers1