Add tstops support via LSODA's tcrit mechanism#78
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ChrisRackauckas merged 5 commits intoMar 25, 2026
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Use itask=4/5 with opt.tcrit to prevent the solver from stepping past user-specified tstops times. This enables correct handling of discontinuities in the RHS without requiring callbacks. - Merge tstops into integration targets, track save points separately - Gate saves on save_everystep || is_save_point - Fall back to non-tcrit itask after all tstops are passed - Add tests for tstops with saveat, save_everystep, 2D problems, boundary filtering, and discontinuous RHS accuracy Co-Authored-By: Chris Rackauckas <accounts@chrisrackauckas.com> Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
When tcrit is set to a tstop target, the solver is guaranteed not to overstep it, so use a simpler loop without overstep/interpolation handling. The overstep path is only needed for saveat-only targets between tstops (itask=5 can still overshoot those). Co-Authored-By: Chris Rackauckas <accounts@chrisrackauckas.com> Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
- Always include T (end time) in tstops so the solver never steps past it. This eliminates the "don't overstep the last timestep" hack and always uses itask=4/5 with tcrit. - Split the else branch (already past target) for tstops vs saveat: tstop targets just save (already there), saveat targets interpolate. - Accept d_discontinuities kwarg and merge into tstops. Remove d_discontinuities from warnlist since it is now supported. Co-Authored-By: Chris Rackauckas <accounts@chrisrackauckas.com> Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Direct mapping: dtmin → opt.hmin, dtmax → opt.hmax. Removed dtmin/dtmax from warnlist. Co-Authored-By: Chris Rackauckas <accounts@chrisrackauckas.com> Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
actions/checkout v2→v4, setup-julia v1→v2, actions/cache v1→v4, codecov-action v1→v4. The v1 cache action was causing immediate CI failures. Co-Authored-By: Chris Rackauckas <accounts@chrisrackauckas.com> Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
ChrisRackauckas
approved these changes
Mar 25, 2026
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Summary
tstopserror with actual support using LSODA's built-intcritmechanism (itask=4/5)tstopsinto integration targets while tracking which times are save points, sotstopscontrols solver stepping without affecting outputHow it works
The LSODA C library supports
itask=4(integrate to tout, don't step pasttcrit) anditask=5(one step, don't step pasttcrit). This PR leverages these modes to implementtstops:tstopstimes are merged withsaveattimes into a combined list of integration targetssave_settracks which targets should produce output (onlysaveattimes)opt.tcritis set to the next upcoming tstopsave_everystep || is_save_pointTest plan
tstopswithsaveatproduces correct save timeststopswithsave_everystep=trueincludes tstop times in outputsave_everystep+saveat+tstops🤖 Generated with Claude Code