v9.19.0

ModelingToolkit v9.19.0

Diff since v9.18.1

Merged pull requests:

• Fix specialize overdetemined system in tearing (#2803) (@YingboMa)

Closed issues:

• Niche case of plotsol; idxs = [...]) fails (#2778)

v9.18.1

ModelingToolkit v9.18.1

Diff since v9.18.0

Merged pull requests:

• Remove componentarrays (#2800) (@ChrisRackauckas)
• Use NAMESPACE_SEPARATOR (#2801) (@YingboMa)
• Revert "Bye bye ₊, use var symbols with ." (#2802) (@YingboMa)

v9.18.0

ModelingToolkit v9.18.0

Diff since v9.17.1

Merged pull requests:

• refactor: directly solve initialization problem in linearization_function (#2762) (@AayushSabharwal)
• Better over-determined tearing (#2793) (@YingboMa)
• refactor: use common implementation of observedfun (#2796) (@AayushSabharwal)
• Bye bye ₊, use var symbols with . (#2798) (@ChrisRackauckas)

Closed issues:

• providing updated op to linearization_function has no effect (#2784)
• Initialization is incomplete without a u0, despite passing guesses (#2788)

v9.17.1

ModelingToolkit v9.17.1

Diff since v9.17.0

Merged pull requests:

• allow for late binding of initialization equations (#2789) (@ChrisRackauckas)
• feat: store observed equation lhs in symbol_to_variable mapping (#2791) (@AayushSabharwal)

Closed issues:

• Unknowns in the initialization_eqs should be added to the variable list (#2787)
• remake SteadyStateProblem gives different solution (#2790)
• Cannot initialize system with default that depends on observed variable (#2792)

v9.17.0

ModelingToolkit v9.17.0

Diff since v9.16.0

Merged pull requests:

• Add initialization_equations flattening constructor (#2591) (@ChrisRackauckas)
• Fixes for dependent parameters (#2668) (@SebastianM-C)
• error for hybrid continuous/discrete systems (#2765) (@baggepinnen)
• feat: allow specifying variable names in modelingtoolkitize (#2768) (@AayushSabharwal)
• Remove unnecessary line in calculate_massmatrix function (#2771) (@bowenszhu)
• fix: fix build_explicit_observed_function for array parameter expressions (#2772) (@AayushSabharwal)
• Fix typos (#2773) (@ChrisRackauckas)
• Add propagation of guesses from parameters and observed (#2775) (@ChrisRackauckas)
• Fix accessing of defaults in BifurcationKit extensions (#2776) (@TorkelE)
• Fix unnecessary type specification in BK extension (#2777) (@TorkelE)
• Test parameters + defaults in initialization propagation (#2781) (@ChrisRackauckas)
• Only use the observed for simplification in MTKParameters construction (#2783) (@ChrisRackauckas)
• fix: avoid infinite loops in MTKParameters initialization (#2785) (@AayushSabharwal)

Closed issues:

• Cannot solve for dependent parameters during initialization (#2665)
• Remake fails with mixed variable and parameter defaults (#2715)
• Initialization systems don't support parametric guesses (#2716)
• ForwardDiff fails to differentiate ODE, due to type error between tspan and u0 (#2721)
• Pass state and parameter names etc. to modelingtoolkitize so the equations are easier to compare (#2736)
• getu with vector observed fails (#2767)
• New parameter type validation broke parameter splines (#2769)
• Cannot initialize unknown from observed that depends on parameter (#2774)

v9.16.0

ModelingToolkit v9.16.0

Diff since v9.15.0

Merged pull requests:

• feat: add parameter type and size validation in remake_buffer and setp (#2657) (@AayushSabharwal)
• fix: create and solve initialization system in linearization_function (#2676) (@AayushSabharwal)
• feat: relax type restrictions in MTKParameters construction (#2686) (@AayushSabharwal)
• Backport #2719 to MTK v8 (#2726) (@devmotion)
• fix: fix bug in remake_buffer (#2729) (@AayushSabharwal)
• CompatHelper: add new compat entry for DeepDiffs in [weakdeps] at version 1, (keep existing compat) (#2737) (@github-actions[bot])
• CompatHelper: add new compat entry for BifurcationKit in [weakdeps] at version 0.3, (keep existing compat) (#2738) (@github-actions[bot])
• Update to SymbolicUtils v2 (#2760) (@ChrisRackauckas)
• fix: error when simplified discrete system contains algebraic equations (#2766) (@AayushSabharwal)

Closed issues:

• Indexing and iterating in ODEProblem and modelingtoolkitize / error messages (#1678)
• Cannot beat OpenModelica score with ModelingToolkit.jl and OrdinaryDiffEq.jl (#1693)
• OOM on cyclical network (#2015)
• ForwardDiff does not work directly through ODEProblem (#2667)
• Error about missing parameter to ODEProblem reports it as a missing initial condition (#2694)
• Using mixed data types with the remake function will lead to an error. (#2713)
• DiscreteProblem without and with ifelse (#2718)
• MTK doesn't precompile on my Windows 11 laptop anymore (#2730)
• Unknowns of full sys used instead of for discrete partition (#2732)
• split=false required to simulate with uncertain parameters (#2746)
• Bad latex display for equations with vector variables: (#2752)
• Use Terminterface.iscall isntead of istree (#2753)
• SDE simulations broken (#2754)
• SDE simulation broken again (#2756)
• Vector parameters don't work with parameter_dependencies (#2764)

v8.76.0

ModelingToolkit v8.76.0

Diff since v8.75.0

Merged pull requests:

• [BREAKING Don't merge] Support DynamicQuantities (#2349) (@YingboMa)
• add component-based hybrid system test (#2355) (@baggepinnen)
• Add support for component array in @mtkmodel (#2368) (@ven-k)
• Getcoeffchunk (#2393) (@chriselrod)
• Preserve staticarrays in the problem construction (#2399) (@ChrisRackauckas)
• Fix up initializesystem for hierarchical models (#2403) (@ChrisRackauckas)
• Fix some warnings (#2405) (@isaacsas)
• add docs for sampled-data systems (#2410) (@baggepinnen)
• build(deps): bump crate-ci/typos from 1.16.25 to 1.17.0 (#2419) (@dependabot[bot])
• CompatHelper: bump compat for DynamicQuantities to 0.11, (keep existing compat) (#2424) (@github-actions[bot])
• Replace MacroTools with ExprTools & Base.remove_lines! (#2425) (@oxinabox)
• Add event support mtkmodel (#2427) (@cgutsche)
• Consistent variable creation (#2428) (@YingboMa)
• build(deps): bump actions/cache from 3 to 4 (#2430) (@dependabot[bot])
• fix(pdesystem): parameters are vector of Num instead of vector of pairs when analytic is also passed (#2431) (@sathvikbhagavan)
• refactor: rename states to unknowns, and related changes (#2432) (@AayushSabharwal)
• feat!: deprecate ODAEProblem (#2435) (@AayushSabharwal)
• refactor!: require systems to be completed before creating XProblem/XProblemExpr (#2436) (@AayushSabharwal)
• feat: add @defaults to @mtkmodel (#2437) (@ven-k)
• Fix updating default value metadata of conditional parameters (#2438) (@ven-k)
• test: uncomment tests (#2439) (@AayushSabharwal)
• refactor!: remove old discrete system (#2440) (@AayushSabharwal)
• Add StateMachineOperators (#2441) (@YingboMa)
• feat!: add common definitions of t and D (#2442) (@AayushSabharwal)
• fix!: require explicit independent variable for ODESystem (#2443) (@AayushSabharwal)
• Update bifurcation_diagram_computation.md (#2444) (@rveltz)
• Update bifurcation_diagram_computation.md, add periodic orbits comput… (#2445) (@rveltz)
• chore: remove undefined exports (#2446) (@sathvikbhagavan)
• feat!: use SciMLStructures and add new MTKParameters (#2447) (@AayushSabharwal)
• build(deps): bump codecov/codecov-action from 3 to 4 (#2448) (@dependabot[bot])
• build(deps): bump crate-ci/typos from 1.17.0 to 1.18.0 (#2449) (@dependabot[bot])
• Have CI tests depend on formatter passing (#2451) (@chriselrod)
• [skip ci] Update dependabot.yml (#2452) (@ArnoStrouwen)
• ci: explicitly specify token for codecov (#2454) (@thazhemadam)
• Pin JuliaFormatter (#2456) (@YingboMa)
• docs: use @mtkbuild instead of manually calling complete (#2460) (@AayushSabharwal)
• Fix test groupings and test setup (#2465) (@ChrisRackauckas)
• docs: update NEWS.md with v9 update notes (#2466) (@AayushSabharwal)
• build: bump compat of DomainSets (#2467) (@sathvikbhagavan)
• Correct number of srcs in complete (#2468) (@Keno)
• feat!: do not scalarize parameters, fix some tests (#2469) (@AayushSabharwal)
• Format (#2471) (@YingboMa)
• docs: update NEWS.md (#2473) (@AayushSabharwal)
• Fix and update documentation for v9 (#2478) (@ChrisRackauckas)
• chore: add 0.12 of DynamicQuantities (#2479) (@ven-k)
• fix: fix jacobian generation for NonlinearSystem (#2480) (@AayushSabharwal)
• CompatHelper: bump compat for DiffEqCallbacks to 3, (keep existing compat) (#2486) (@github-actions[bot])
• CompatHelper: bump compat for ModelingToolkit to 9 for package docs, (keep existing compat) (#2487) (@github-actions[bot])
• docs: update docs for MTKv9 (#2489) (@AayushSabharwal)
• OptimizationSystem: Generate oop constraint derivatives (#2492) (@Vaibhavdixit02)
• SelectedUnknown -> SelectedState (#2494) (@YingboMa)
• Fix testing infrastructure (#2495) (@ChrisRackauckas)
• CompatHelper: bump compat for DynamicQuantities to 0.12 for package docs, (keep existing compat) (#2498) (@github-actions[bot])
• Parse constants in @mtkmodel (#2499) (@ven-k)
• Provision to enforce types in parameters, variables and structural_parameters in @mtkmodel (#2500) (@ven-k)
• Improve handling of expression in metadata (#2501) (@ven-k)
• Update NEWS.md for DAE Initialization changes (#2503) (@ChrisRackauckas)
• feat: initial implementation of new DiscreteSystem (#2507) (@AayushSabharwal)
• Expose a non dummy derivative index lowering (#2510) (@ChrisRackauckas)
• 🚑 pass type to var generation (#2511) (@ven-k)
• Initialization on non-DAE models (#2512) (@ChrisRackauckas)
• fix: fix variable_index (#2514) (@AayushSabharwal)
• feat: add SolverStepClock (#2517) (@baggepinnen)
• Add a tutorial for initialization handling (#2518) (@ChrisRackauckas)
• Add init for maximum (#2519) (@YingboMa)
• fix: type of array in the mtkmodel's f (#2521) (@ven-k)
• [skip ci] add isconnection to ignored typos words (#2523) (@ArnoStrouwen)
• fix: avoid scalarizing params in structural_simplify, variable defaults in get_u0 (#2524) (@AayushSabharwal)
• Add getindex/setindex! methods for MTKParameters with ParameterIndex (#2531) (@MasonProtter)
• Specialize symbolic Struct (#2532) (@YingboMa)
• Avoid computing inputs if IO is unspecified (#2537) (@baggepinnen)
• fix: fix history function in DDEProblem constructor (#2541) (@AayushSabharwal)
• docs: update FAQ section with relevant MTKv9 questions (#2542) (@AayushSabharwal)
• refactor: implement new additions to SII interface (#2544) (@AayushSabharwal)
• Fix _varmap_to_vars, re-enable dde.jl test (#2545) (@MasonProtter)
• fix: fix io handling in structural_simplify, input_output_handling tests (#2547) (@AayushSabharwal)
• fix: do not filter array unknowns in wrap_array_vars (#2549) (@AayushSabharwal)
• Fix iteration bounds in tearing_with_dummy_derivatives (#2557) (@YingboMa)
• Add missing updates to sampled-data docs (#2560) (@baggepinnen)
• Update for StructuralIdentifiability API changes (#2561) (@ChrisRackauckas)
• Update DynamicQuantities compatibility (#2562) (@TorkelE)
• feat: allow parameter defaults to depend on initial values of unknowns (#2563) (@AayushSabharwal)
• fix: fix creation of JumpProblems with no parameters (#2564) (@AayushSabharwal)
• Document and export continuous_events and discrete_events (#2567) (@MasonProtter)
• refactor: use the t defined in the module (#2569) (@ven-k)
• feat: implement SII.remake_buffer for MTKParameters, fix bugs, add tests (#2570) (@AayushSabharwal)
• initialization bypass (#2572) (@ChrisRackauckas)
• Handle derivatives of observed variables (#2574) (@ChrisRackauckas)
• fix: fix initialization and observed bugs (#2575) (@AayushSabharwal)
• test: add MTKParameters tests, fix bugs (#2581) (@AayushSabharwal)
• Empty events should be empty (#2582) (@YingboMa)
• fix: fix varmap_to_vars for variables with unspecified size (#2586) (@AayushSabharwal)
• Fix tearing_reassemble for under-determined systems (#2587) (@YingboMa)
• refactor: remove undefined export initializesystem (#2588) (@sathvikbhagavan)
• fix: fix hierarchical discrete systems (#2593) (@AayushSabharwal)
• fix: fix namespacing of defaults and equations (#2594) (@AayushSabharwal)
• Revert "fix: fix namespacing of defaults and equations" (#2595) (@ChrisRackauckas)
• Change wording from initial guess to initial condition (#2598) (@baggepinnen)
• docs: add tutorial for optimizing ODE solve and remake (#2600) (@AayushSabharwal)
• Accessors for differential and algebraic erquations (#2601) (@TorkelE)
• Support docstrings for @connectors and @components (#2602) (@devmotion)
• fix: fix variable namespacing issues (#2603) (@AayushSabharwal)
• fix: fix callback codegen, observed eqs with non-scalarized symbolic arrays (#2605) (@AayushSabharwal)
• refactor: improve replace, remake_buffer (#2610) (@AayushSabharwal)
• Speed up replace and canonicalize by improving type stability (#2613) (@SebastianM-C)
• feat: improve error messages for missing variables and subsystems (#2617) (@AayushSabharwal)
• Revert "feat: improve error messages for missing variables and subsystems" (#2620) (@YingboMa)
• Revert "feat: improve error messages for missing variables and subsystems" (#2622) (@ChrisRackauckas)
• Fix a minor issue in generate_initializesystem (#2627) (@YingboMa)
• fix: propagate parameter dependencies in extend (#2629) (@SebastianM-C)
• fix: fix intialization of array parameters with unknown size (#2630) (@AayushSabharwal)
• feat: allow creating NonlinearSystem without specifying unknowns/parameters (#2631) (@AayushSabharwal)
• feat: support parameter dependencies for NonlinearSystem (#2632) (@AayushSabharwal)
• feat: support partial updates in remake_buffer (#2633) (@AayushSabharwal)
• Fix steady state problem construction (#2636) (@ChrisRackauckas)
• fix: error when all parameters are not initialized (#2640) (@AayushSabharwal)
• collapse unneed branch (#2641) (@oxinabox)
• fix: fix incorrect indexes of array symbolics (#2647) (@AayushSabharwal)
• fix: implement DiffEqBase.anyeltypedual for MTKParameters (#2649) (@AayushSabharwal)
• fix: fix guesses in hierarchical system, getguess for array variables (#2654) (@AayushSabharwal)
• Allow Array unknowns in OptimizationSystem (#2655) (@Vaibhavdixit02)
• Always attach metadata in similarterm (#2666) (@YingboMa)
• We need to unwrap guesses (#2684) (@YingboMa)
• preserve argument order for structural parameters (#2689) (@baggepinnen)
• add sampletime operator (#2690) (@baggepinnen)
• refactor: remove check_length in the error message of unbalanced system (#2693) (@sathvikbhagavan)
• Fix method redefinition (#2698) (@YingboMa)
• Generalize substitute_sample_time so that other backends and extend it (#2708) (@YingboMa)
• Forward system in ODEFunction expression (#2719) (@devmotion)
• Backport #2719 to MTK v8 (#2726) (@devmotion)
• Drastically reduce the number of imports that are inside @recompile_invalidations (#2734) (@oscardssmith)
• CompatHelper: add new compat entry for DeepDiffs in [weakdeps] at version 1, (keep existing compat) (#2...

v9.15.0

ModelingToolkit v9.15.0

Diff since v9.14.0

Merged pull requests:

• Drastically reduce the number of imports that are inside @recompile_invalidations (#2734) (@oscardssmith)

Closed issues:

• EXCEPTION_ACCESS_VIOLATION error during solving of Differential Equation provided by ModelingToolkit (#2722)

v9.14.0

ModelingToolkit v9.14.0

Diff since v9.13.0

Merged pull requests:

• Forward system in ODEFunction expression (#2719) (@devmotion)

Closed issues:

• Forward MTK system to ODEFunction constructor in ODEFunctionExpr (#2550)

v9.13.0

ModelingToolkit v9.13.0

Diff since v9.12.2

Merged pull requests:

• add sampletime operator (#2690) (@baggepinnen)
• refactor: remove check_length in the error message of unbalanced system (#2693) (@sathvikbhagavan)
• Fix method redefinition (#2698) (@YingboMa)
• Generalize substitute_sample_time so that other backends and extend it (#2708) (@YingboMa)

Closed issues:

• Model linearization fails when no parameter is used (#2400)
• Variables eliminated in structural_simplify are not included in simulation plots (#2678)
• Add sampletime() and clock() operators (#2687)
• Silent and wrong derivatives of observed variables (#2697)
• Implicit variable erroneously required in initial condition (#2703)
• structural_simplify uses metadata of the variables instead of what is passed into the system (#2706)