25 lines
648 B
Markdown
25 lines
648 B
Markdown
---
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title: powerset
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tags: math,list,advanced
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firstSeen: 2020-10-04T13:14:01+03:00
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lastUpdated: 2020-11-02T19:28:27+02:00
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---
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Returns the powerset of a given iterable.
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- Use `list()` to convert the given value to a list.
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- Use `range()` and `itertools.combinations()` to create a generator that returns all subsets.
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- Use `itertools.chain.from_iterable()` and `list()` to consume the generator and return a list.
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```py
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from itertools import chain, combinations
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def powerset(iterable):
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s = list(iterable)
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return list(chain.from_iterable(combinations(s, r) for r in range(len(s)+1)))
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```
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```py
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powerset([1, 2]) # [(), (1,), (2,), (1, 2)]
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```
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