Combinations of list of lists - Printable Version

Combinations of list of lists - Printable Version

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Combinations of list of lists - dannyH - May-14-2018

I have a list of 25 lists of integers:
L = [[1,2,3], [4,5,6], [7,8],[9], …]

I want to create all possible combinations using all the integers from each list:

answer = [[1,4,7,9,...], [2,4,7,9,...], [3,4,7,9,...], [1,5,7,9,...], [2,5,7,9], …]

I tried:

for a in L[0]:
    for b in L[1]:
        for c in L[2]:
            ...
                answer = [a,b,c,d, …]

This works until the line length in IDLE exceeds about 90 characters, then the program refuses to run. Is there any way of using iterators, or any other solution?

RE: Combinations of list of lists - buran - May-14-2018

check itertools.product

RE: Combinations of list of lists - dannyH - May-14-2018

Thanks Buran.

I'm new to itertools, but I'll have a look tomorrow.

Danny

I've just found a thread from heiner55 which solves my problem in 1 line:

https://python-forum.io/Thread-How-to-find-the-number-of-permutations-of-a-list-of-lists

Many thanks for all the help from the forum.

Danny