24 lines
542 B
Markdown
24 lines
542 B
Markdown
---
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title: List difference
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tags: list
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expertise: beginner
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cover: blog_images/frog-blue-flower.jpg
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firstSeen: 2018-01-20T16:16:44+02:00
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lastUpdated: 2020-11-02T19:27:53+02:00
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---
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Calculates the difference between two iterables, without filtering duplicate values.
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- Create a `set` from `b`.
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- Use a list comprehension on `a` to only keep values not contained in the previously created set, `_b`.
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```py
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def difference(a, b):
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_b = set(b)
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return [item for item in a if item not in _b]
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```
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```py
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difference([1, 2, 3], [1, 2, 4]) # [3]
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```
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