22 lines
533 B
Markdown
22 lines
533 B
Markdown
---
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title: Find all matching indexes
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type: snippet
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language: python
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tags: [list]
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cover: tree-roots
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dateModified: 2020-11-02T19:27:53+02:00
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---
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Finds the indexes of all elements in the given list that satisfy the provided testing function.
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- Use `enumerate()` and a list comprehension to return the indexes of the all element in `lst` for which `fn` returns `True`.
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```py
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def find_index_of_all(lst, fn):
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return [i for i, x in enumerate(lst) if fn(x)]
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```
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```py
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find_index_of_all([1, 2, 3, 4], lambda n: n % 2 == 1) # [0, 2]
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```
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