patrick-kidger / patrick-kidger/diffrax

Adjust dense output when using `HalfSolver`.

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bug
Dominant language
Python
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Description

At the moment this is using the dense_info from the larger step but advancing the solution using the two smaller steps:

https://github.com/patrick-kidger/diffrax/blob/1bb90b4b687b497c76c59b4817e4b6f70f476262/diffrax/solver/base.py#L241

But these two values needn't line up, so the resulting collection of dense_infos will define something with slight discontinuities in between steps.

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First steps

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  3. Fork the repository and make your change on a branch.
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Research direction

Start at diffrax/solver/base.py around line 241 and inspect how HalfSolver advances the solution and collects dense_info. Compare the dense output from the larger step with the two smaller steps; done means the resulting dense output is continuous between steps.

Written by the indexing model from the issue text.

Assessment

Tech stack
python
Domain
backend
Issue type
Bug
Difficulty
4/5
Estimated time
3-5 days
Activity status
Stale
Clarity
Mostly clear
Newbie friendliness
35/100

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