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SciML / SciMLSensitivity.jl

A component of the DiffEq ecosystem for enabling sensitivity analysis for scientific machine learning (SciML). Optimize-then-discretize, discretize-then-optimize, adjoint methods, and more for ODEs, SDEs, DDEs, DAEs, etc.
https://docs.sciml.ai/SciMLSensitivity/stable/
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EnzymeVJP often fails is automatic sensealg determination #1001

Open ArnoStrouwen opened 10 months ago

ArnoStrouwen commented 10 months ago

Deleting the sensealg keyword in e.g. this tutorial: https://docs.sciml.ai/SciMLSensitivity/dev/examples/optimal_control/optimal_control/ gives the warning that EnzymeVJP does not work on the problem. However, manually specifying Enzyme, e.g. InterpolatingAdjoint(autojacvec = EnzymeVJP), seems to work fine. The vjp calculation thus differ in the two places?

A first weird thing I found was the use of du in duplicated. https://github.com/SciML/SciMLSensitivity.jl/blob/master/src/concrete_solve.jl#L19

ChrisRackauckas commented 10 months ago

Is there an internal alias check? Try changing one of the du's to a copy and see if that fixes it. Other than that, I don't think there's a difference in the vjps, but there must be if that is failing

ArnoStrouwen commented 10 months ago

Already tried that before, did not work. I'll have to dive deeper into the code.