v9.1.0

ModelingToolkit v9.1.0

Diff since v9.0.1

Merged pull requests:

• Add StateMachineOperators (#2441) (@YingboMa)
• 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])
• SelectedUnknown -> SelectedState (#2494) (@YingboMa)

Closed issues:

• Parameter Identifiability Analysis (#170)
• Block calculations of derivative quantities (#270)
• Nicer parameter indexing (#318)
• NetworkSystem (#341)
• How to remake with a Vector{Pair}? (#472)
• Latexify for ODEs uses inconsistent notation for variables. (#533)
• Comment on terminology: parameter vs. (independent) variable t (#564)
• Symbolic arrays instead of arrays of symbolics (#605)
• Fix and/or test NonlinearSystem conversion from ReactionSystems (#639)
• Better error messages for missing equations in ODESystems (#803)
• Implement combine for inheritance of systems (#807)
• Deprecate gensym naming (#831)
• Default value metadata (#846)
• modelingtoolkitize tutorial: automated sparsity handling (#872)
• Detecting and solving small dense linear subsystems symbolically after tearing (#887)
• Discrete-Time (Sub-)Systems (#894)
• Documenting how to generate namespaced names for AbstractSystem variables (#902)
• Visual model representation and interaction (#918)
• structural_simplify(SDESystem) throws an error (#928)
• Delay differential equation handling (#955)
• Support for DAE's without differential terms (#969)
• logo? (#970)
• Better variable identification (#981)
• State selection (#988)
• exporting MTK model to FMU (#994)
• Creating an "ImageProblem" problem type in MTK (#1012)
• Nested systems with symbolic defaults/initial values don't get de-aliased (#1013)
• Support for derivatives/interpolation with simplified systems? (#1014)
• Nonlinear optimal control tutorial equation inconsistency (#1024)
• ControlSystem without defined loss function (#1041)
• Documentation comments (#1053)
• modelingtoolkitize doesn't work with pre-allocated variables (#1058)
• Dispatchable systems (#1071)
• Add sparsity to ODEProblem on construction (#1087)
• Parameter representation for controls (#1088)
• Variable access feature is very slow (#1102)
• Input & output systems (#1111)
• provide type stable access to ODESolution by Num observed object (#1112)
• Namespacing (#1117)
• Allowing discrete Difference equations in ODESystem (#1122)
• extend forget a variable ... (#1133)
• Supporting multi-clock discrete systems (#1137)
• Using Jacobian sparsity structures of large ODEs/PDEs downstream (#1160)
• addition on Differentials not defined (#1161)
• structural_simplify on DiscreteSystem says "this should never happen" (#1166)
• PDESystem fails (#1179)
• Coupling MTK with time discrete control (#1180)
• Problem with 2D Poisson-Eqn. PDE (#1204)
• Difference Operator Not Working Correctly (#1206)
• Error when inverting matrix of dependent variables (#1231)
• StructuralIdentifiability tutorial? (#1232)
• release notes / news equivalent for breaking changes or new features (#1245)
• Functions created by build_function should supported passing parameters using NamedTuples and Dicts (#1259)
• parameters in modelingtoolkit don't support vector ? (#1271)
• incorrect ODEs when child ODESystem contains ParentScope'd state (#1274)
• Documentation (#1280)
• Example of potential compile time growth issue (#1286)
• very slow when rebuild ODEProblem (#1285)
• Dimension problem for the variable multiplication (#1291)
• Support for finding nullclines (#1294)
• StackOverflowError, can't handle large system (#1297)
• Error when simulating ODESystem with difference equations (#1304)
• Time-shift operator for discrete-time control systems (#1307)
• How to preserve compilation of observed runtime generated function? (#1312)
• Algebraic equations are delayed one step too much in DiscreteSystems (#1330)
• Incorrect observed variables after structural_simplify (#1345)
• Tutorial for Spring-Mass-System resulting in Stack Overflow Error (#1353)
• Tearing partitioning doesn't consider solvability (#1362)
• Solving errors (#1365)
• Some symbolic parameters are not replaced by numeric during solve (#1369)
• Automatic inference of time step for DiscreteSystems (#1374)
• Incorrect solution for DiscreteSystem (#1378)
• Unable to build torn function (#1379)
• Use tearing information directly in codegen (#1387)
• Inputs outputs in MTK (#1411)
• Spring-mass tutorial fails on MTK v8.3.2 (#1434)
• ODAEProblem should try to transform mass matrices to the identity matrix (#1435)
• Parameter Identifiability in ODE Models (#1441)
• Using structural_simplify on SDE System (#1447)
• docs for full_equations() (#1459)
• Long compilation time some numbers + included examples (#1461)
• Easier vectorial differential equations (#1485)
• Julia REPL crash when using NewtonRaphson on a semi-big problem (#1507)
• mul_float: types of a and b must match error in ModelingToolkit (#1515)
• Allow extend System to override previous equations (#1518)
• Support for scalar parameter and initial condition mappings (#1520)
• How to represent Modelica style If-Equations using MTK (#1523)
• UndefRefError When modelingtoolkitizeing a system that uses DEDataArrays (#1564)
• Slow access to solution via symbols (#1585)
• Implicit DAE observed indexing is broken (#1589)
• Constructing an ODEProblem with a non-numeric parameter throws a Float conversion error. (#1595)
• Difference ODEProblem ODAEProblem (#1611)
• Compatibility with DataInterpolations.jl (#1615)
• ODAE problem does not acknowledge retcodes when solving (#1633)
• Passing initial state of submodel silently fails (#1638)
• Latex rendering issues (#1658)
• sparsity pattern J vs J-gamma*I (#1668)
• MTK cannot identify independent variables with new Symbolics convention (#1706)
• Vector parameters not supported (#1723)
• ODAEProblem's observed function is not always topologically sorted (#1726)
• Indexing solutions with many symbolics fails (#1737)
• Handling of wrongly namespaced variables (#1746)
• Homogenize parameters by default (#1748)
• Symbolic variables don't work for several inbuilt functions (#1749)
• Optimization tutorial fails (#1781)
• Sanity type-checking for equations (#1788)
• Crashing REPL w/ malformed system (#1801)
• ODEProblem creation fails for Unitful models (#1803)
• DtLessThanMin when solving Mixed Difference Differential Equations test example (#1809)
• feature request: make remake take partial parameter maps (#1810)
• Unit checking error message (#1813)
• State reordering on structural_simplify (#1817)
• Update the var_to_name map when vars are updated (#1825)
• Cannot determine ordering of Dual tags ForwardDiff (#1867)
• solution indexing with symbolic expressions that include parameters (#1874)
• MTK -- basic questions (#1925)
• thoughts on being stricter when constructing Problems from systems? (#1933)
• Symbolic indexing of the solution is slow (#1944)
• Vsode ParseError: KaTeX parse error: (#1958)
• UndefVarError when retrieving solution of ODAEProblem without prior index lowering (#1961)
• getproperty incompatible with ParentScope and DelayParentScope (#1973)
• Conductor as a downstream test on MTK (#1979)
• paramters in optimizations FAQ (#1982)
• Cryptic Tsit5() error message when building a simple electrical circuit (#2006)
• Unexpected UndefVarError (#2007)
• Variable metadata connector documentation (#2013)
• Simulation of hybrid system (#2018)
• Compilation of ODEProblem generated from MTK system fails on GPU even if original problem is GPU-compatible (#2026)
• MTK: Scaling of time/parametric plots? (#2076)
• Composable NonlinearSystem fails but runs as an ODESystem (#2106)
• structural_simplify unexpected ERROR when applied twice in a row (#2108)
• Not an issue... but trying to understand MTK (#2111)
• Indexing solution with symbolic array is slow (#2112)
• Q: parameters in MTK (#2130)
• MTK Bug? Some observed are not computed? (#2136)
• Enable `solve(...;save_idxs=) for not integer indexes (#2139)
• Possible regression when simplifying system to 0 states (#2141)
• Discrete systems in MTK (#2165)
• Incomplete derivative expansion with DataInterpolations (#2169)
• remake doesn't work with mapped parameters (#2171)
• [FR] Allow named container for parameters when converting to DEProblem (#2195)
• Documentation tab for various API function (#2224)
• Add more complete DynamicQuantities support (#2230)
• Handling of dependent defaults (#2238)
• Split tunables from the rest of heterogeneous parameter (#2260)
• Add tunables in ODEProblems (#2261)
• Next major release checklist (#2262)
• Array parameters/variables with @mtkmodel (#2269)
• Recent bug: parameter tuples no longer preserve parameter types (#2296)
• Do not split parameters into tuple of vectors by default (#2311)
• Improve documentation (#2326)
• Inconsistency in structural_parameters and non-contextualized error message (#2341)
• ERROR: ArgumentError: System rc_model: variable resistor₊v does not exist (#2369)
• Deprication of all_dimensionless and how to adapt unit check in Catalyst? (#2459)
• MTK 9 migration guide (#2463)
• System can't structural_simplify when using multiple SampledData blocks (#2475)