23 lines
607 B
Markdown
23 lines
607 B
Markdown
---
|
|
title: powerset
|
|
tags: math,list,advanced
|
|
---
|
|
|
|
Returns the powerset of a given iterable.
|
|
|
|
- Use the `list()` constructor to convert the given value to a `list`.
|
|
- Use `range()` and `combinations()` to create a generator the returns all subsets.
|
|
- Use `chain.from_iterable()` and the `list()` constructor to consume the generator and return a list.
|
|
|
|
```py
|
|
from itertools import chain, combinations
|
|
|
|
def powerset(iterable):
|
|
s = list(iterable)
|
|
return list(chain.from_iterable(combinations(s, r) for r in range(len(s)+1)))
|
|
```
|
|
|
|
```py
|
|
powerset([1, 2]) # [(), (1,), (2,), (1, 2)]
|
|
```
|