numpy / numpy/numpy

BUG: indexing helpers np.r_, np.mgrid, and np.ogrid give nonsense results for stop-less slices

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00 - Bug defunct — difficulty: Intermediate
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Python
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Description

np.r_[:3] == [0, 1, 2] is fine, but np.r_[3:] == [0, 1, 2] makes no sense at all

>>> np.r_[3:]
array([0, 1, 2])
>>> np.ogrid[3:]
array([0, 1, 2])
>>> np.mgrid[3:]
array([0, 1, 2])

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First steps

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  4. Open a pull request that references the issue number.

Research direction

Start by reproducing the stop-less slice examples for np.r_, np.mgrid, and np.ogrid, then trace the indexing-helper entry points that handle these slices. Clarify the intended behavior for slices such as 3: and add regression coverage showing that the helpers no longer return nonsensical results.

Written by the indexing model from the issue text.

Assessment

Tech stack
python
Domain
data
Issue type
Bug
Difficulty
3/5
Estimated time
1-2 days
Activity status
Stale
Clarity
Mostly clear
Newbie friendliness
35/100

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