Fix overdetermined initialization in Element1D and ConvectiveElement1D#433
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AayushSabharwal merged 1 commit intoSciML:mainfrom Jan 27, 2026
Merged
Fix overdetermined initialization in Element1D and ConvectiveElement1D#433AayushSabharwal merged 1 commit intoSciML:mainfrom
AayushSabharwal merged 1 commit intoSciML:mainfrom
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In MTK v11, the syntax `dT(t) = dT` with a constant value creates an initial_condition, which adds an initialization equation. For algebraic variables like `dT` and `Q_flow` that are constrained by equations (e.g., `dT ~ port_a.T - port_b.T`), this creates an overdetermined initialization system. The fix changes from initial conditions to guesses: - Old: `dT(t) = dT, [guess = 0.0]` (dT arg as initial condition) - New: `dT(t), [guess = dT_guess]` (dT_guess arg as guess only) This follows the MTK v11 semantics where algebraic/observed variables should only have guesses, not initial conditions. Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
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In MTK v11, the syntax
dT(t) = dTwith a constant value creates aninitial_condition, which adds an initialization equation. For algebraic
variables like
dTandQ_flowthat are constrained by equations(e.g.,
dT ~ port_a.T - port_b.T), this creates an overdeterminedinitialization system.
The fix changes from initial conditions to guesses:
dT(t) = dT, [guess = 0.0](dT arg as initial condition)dT(t), [guess = dT_guess](dT_guess arg as guess only)This follows the MTK v11 semantics where algebraic/observed variables
should only have guesses, not initial conditions.
Co-Authored-By: Claude Opus 4.5 noreply@anthropic.com
Checklist
contributor guidelines, in particular the SciML Style Guide and
COLPRAC.
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