Python - Generate list of lists from other list values

Question

I need to generate a list of lists in that special way:

[3, 1, 4] -> [[1, 2, 3], [1], [1, 2, 3, 4]]

That means that every list in a list of lists must be in range of the given list values. I've tried smth like:

L = [3, 1, 4]
q = [i for i in L]
print(list([x] for x in range(y for y in q)))

But it return a TypeError: generator cannot be interpreted as an integer

That all has to be a single generator expression.

Rakesh · Accepted Answer · 2018-06-01 13:05:51Z

0

Using a list comprehension.

Try:

L = [3, 1, 4]
print([list(range(1, i+1)) for i in L])

Output:

[[1, 2, 3], [1], [1, 2, 3, 4]]

answered Jun 1, 2018 at 13:05

Rakesh

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2 Comments

That works! Thank you a lot. Could you please explain me the construction of list(range())? (Just a little bit)

In python3 range is a generator. that is why I am encapsulating it in list. if I do not do that you will get a generator expression