`rand!` is marked non-differentiable

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#603 opened on Mar 28, 2022 2 comments 0 reactions 0 assignees View on GitHub

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Dominant language: Julia
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Description

This fallback method for rand in Distributions.jl hits this rule, which is declared non-differentiable.

This results in a silent failure, where there ought to be an error if the given AD (in my case Zygote), is unable to handle in-place differentiation.

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Research direction

Start with the fallback method linked in Distributions.jl's src/genericrand.jl and the random rule at src/rulesets/Random/random.jl. Reproduce the rand! differentiation case with an AD such as Zygote and trace why it is treated as non-differentiable. Done means the unsupported in-place differentiation case no longer fails silently and its behavior is covered by a regression check.

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Assessment

Tech stack: julia
Domain: devtools
Issue type: Bug
Difficulty: 3/5
Estimated time: 1-2 days
Activity status: Stale
Clarity: Mostly clear
Newbie friendliness: 45/100

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