ModelingToolkitBase-v1.69.0

ModelingToolkitBase ModelingToolkitBase-v1.69.0

Diff since ModelingToolkitBase-v1.68.3

• Adds the public names calculate_paramjac and generate_paramjac.
• Adds a tspan field to System, so a system can carry its own time span, and every time-dependent problem constructor (ODEProblem, DAEProblem, DDEProblem, SDEProblem, SDDEProblem, BVProblem, DiscreteProblem, ImplicitDiscreteProblem) falls back to it when the caller omits one. Omitting it for a system without one throws MissingTspanError. JumpProblem keeps its required time span, because a two-argument method would be ambiguous with JumpProcesses.JumpProblem(prob, jumps...). This adds no new accessor: get_tspan and has_tspan already existed and were already public.

🤖 Posted by an AI agent (Claude Code, model claude-opus-5) on behalf of Chris Rackauckas.

https://claude.ai/code/session_01H5RuLDtEazwTKPkNbPeZVu

Merged pull requests:

• [bot] Solve implicit affects at the ODE solver's tolerance (#5080) (@ChrisRackauckas)
• Document observed access and plotting from a live integrator (#5081) (@ChrisRackauckas-Claude)
• Add analytical parameter jacobian code generation (#5083) (@AJ0070)
• Default every time-dependent problem constructor to the system's tspan (#5085) (@ChrisRackauckas-Claude)
• Release ModelingToolkitBase 1.69.0 (#5086) (@ChrisRackauckas)
• Recommend the inputs keyword for interactive external signals (#5087) (@ChrisRackauckas-Claude)
• Document unbound_inputs as the fallback for discovering an input (#5090) (@ChrisRackauckas-Claude)

Closed issues:

• Symbolic tspan (#847)