Op 2/03/2022 om 14:44 schreef Larry Martell:
On Wed, Mar 2, 2022 at 8:37 AM Antoon Pardon<antoon.par...@vub.be> wrote:
Op 2/03/2022 om 14:27 schreef Larry Martell:
On Tue, Mar 1, 2022 at 7:21 PM<2qdxy4rzwzuui...@potatochowder.com> wrote:
On 2022-03-01 at 19:12:10 -0500,
Larry Martell<larry.mart...@gmail.com> wrote:
If I have 2 lists, e.g.:
os = ["Linux","Windows"]
region = ["us-east-1", "us-east-2"]
How can I get a list of tuples with all possible permutations?
So for this example I'd want:
[("Linux", "us-east-1"), ("Linux", "us-east-2"), ("Windows",
"us-east-1"), "Windows", "us-east-2')]
The lists can be different lengths or can be 0 length. Tried a few
different things with itertools but have not got just what I need.
[(o, r) for o in os for r in region]
This does not work if region = []. I wrote in my question that either
list could be empty.
What do you mean it doesn't work? The result seems to be an empty list,
which IMO is a perfectly valid result.
All possible permutations over two collections where one collection is
empty, should IMO give you an empty collection.
If one list is empty I want just the other list. What I am doing is
building a list to pass to a mongodb query. If region is empty then I
want to query for just the items in the os list. I guess I can test
for the lists being empty, but I'd like a solution that handles that
as down the road there could be more than just 2 lists.
How about the following: Keep a list of your lists you want to permute over.
Like the following:
permutation_elements = [["Linux","Windows"],["us-east-1", "us-east-2"]]
permutation = itertools.product(*permutation_elements)
If you don't include the empty list, you will get more or less what you
seem to want.
Antoon Pardon.
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