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ParallelRange with Sliced Matrix

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#162 7 comments 0 reactions 0 assignees View on GitHub

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Assessment

Difficulty
3/5
Estimated time
1-2 days
Newbie friendliness
38/100
Issue type
Bug
Clarity
Mostly clear
Activity status
Stale
Tech stack
python
Domain
backend, hpc

Research direction

Start by running the provided ParallelRange reproducer with the sliced right[:,:,ii] input and compare it with the standalone matmul that succeeds. Trace the ParallelRange and matmul entry points to find where the slice dimensions are handled; done means the looped matmul completes without failure and produces the expected result shape.

Written by the indexing model from the issue text.

Description

If you slice a matrix in the ParallelRange matmul does not detect the change in dimension and fails:

res = af.constant(0,20,20,1000 )    
left = af.constant(0, 20, 40)
right = af.constant(0, 40,20, 1000)

af.matmul(left, right[:,:,0]) # this works
for ii in af.ParallelRange(10):
            res[:,:,ii] = af.matmul(left, right[:,:,ii]) #will fail
Dominant language
Python
Stars
422
Forks
63
No merged PRs in 30d

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