v11.45.2

ModelingToolkit v11.45.2

Diff since v11.45.1

• Fall back to the unlowered residual when the steady-state SCC lowering is structurally singular: #5197
• Handle SCCNonlinearProblem with no remaining unknowns: #5183
• fix: keep connector types in NonlinearSystem and transfer only valid Initial values in steady-state SCC lowering: #5208

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Merged pull requests:

• refactor: improve new array-form codegen (#5157) (@AayushSabharwal)
• Fix dead PDEBase link in PDESystem docs (#5167) (@ChrisRackauckas-Claude)
• Fix SampleTime operator (#5175) (@kpamnany)
• Handle SCCNonlinearProblem with no remaining unknowns (#5183) (@ChrisRackauckas-Claude)
• Reconstruct whole arrays in the SCC CacheWriter when prior states are views (#5184) (@ChrisRackauckas-Claude)
• Broadcast scalars to array keys in write_possibly_indexed_array! (#5186) (@AayushSabharwal)
• Lower array-valued constraints into cons/lcons/ucons (#5189) (@ChrisRackauckas-Claude)
• Fix initialization for residual array-slice equations (#5191) (@ChrisRackauckas-Claude)
• Fall back to the unlowered residual when the steady-state SCC lowering is structurally singular (#5197) (@SebastianM-C)
• Keep the sparse ODE Jacobian within the pattern of its prototype (#5198) (@SebastianM-C)
• Skip nameless entries in propertynames/getvar of AbstractSystem (#5204) (@ChrisRackauckas-Claude)
• Fix steady-state SCC lowering for hierarchical models with connectors and for array unknowns (#5208) (@avinashresearch1)
• Return a vector from a root CopyParamsByTemplate with a single entry (#5209) (@baggepinnen)
• Fix saved_clock_partitions for array-valued continuous events (#5220) (#5222) (@ChrisRackauckas-Claude)
• Bump ModelingToolkitBase to 1.77.1 and ModelingToolkit to 11.45.2 (#5228) (@ChrisRackauckas)

Closed issues:

• REPL tab completion of system with Differential state throws exception (#923)
• write_possibly_indexed_array! should broadcast scalar values to array-shaped keys (remove write_dd_guess!) (#5147)
• Lower array-valued constraints of a System into cons/lcons/ucons (#5151)
• SteadyStateProblem SCC lowering throws ExtraEquationsSystemException inside solve (also for DynamicSS) on structurally singular residuals (#5177)
• SCCNonlinearProblem with no remaining unknowns fails in ForwardDiff (chunk size 1 > structural length 0) (#5179)
• SCC CacheWriter leaves whole arrays unbound when prior state symbols are views (#5180)
• Array-valued continuous-event conditions that modify a discrete array hit a BoundsError in save_discretes! at the third root (#5220)