Update OrdinaryDiffEq requirement from 6 to 6, 7.0

[dependabot]

Updates the requirements on OrdinaryDiffEq to permit the latest version.

Release notes

Sourced from OrdinaryDiffEq's releases.

v7.0.0

OrdinaryDiffEq v7.0.0

Diff since v6.211.0

Many breaking changes. The complete migration story is detailed in https://github.com/SciML/OrdinaryDiffEq.jl/blob/master/NEWS.md

Merged pull requests:

• Fix the interpolation function for dense output (#11) (@​dawbarton)
• Merge Internal Redesign (#18) (@​ChrisRackauckas)
• v0.6 compatibility (#37) (@​ChrisRackauckas)
• WIP: SSPRK (#40) (@​ranocha)
• no test prob and callbacks in prob (#41) (@​ChrisRackauckas)
• Compat.Iterators needs 0.18 minimum (#44) (@​tkelman)
• Add testing with v0.6 on Travis and AppVeyor (#47) (@​ScottPJones)
• Remove InplaceOps, no longer used (#51) (@​ScottPJones)
• ode_interpolant uses @evalpoly in interpolants.jl (#52) (@​ranocha)
• rewrote ode_dense_test.jl to make it more readable (#53) (@​ranocha)
• Add first derivatives for interpolation (#54) (@​gabrielgellner)
• Update CI URLs to point to new caching infrastructure (#56) (@​staticfloat)
• update minimum julia version to 0.6.0-pre (#57) (@​tkelman)
• Add dense SSP output for SSPRK22 and SSPRK33 (#65) (@​ranocha)
• added SSPRK432 incl. 2nd order SSP dense output (#66) (@​ranocha)
• Remove type of integrator in signature of apply_discrete_callback! (#67) (@​devmotion)
• Improvements of SSPRK methods (#68) (@​ranocha)
• [WIP] High order symplectic integrator (#69) (@​YingboMa)
• Fix for element-wise tolerances (#71) (@​devmotion)
• Add third-order symplectic integrator (#73) (@​YingboMa)
• Make the output of a solution interpolation be a DiffEqArray (#74) (@​gabrielgellner)
• Sanitize tstops (#76) (@​devmotion)
• Avoid undefined entries if k is array of arrays (#80) (@​devmotion)
• Fix deprecation warning for isnan (#81) (@​devmotion)
• [WIP] Add Runge-Kutta-Nyström method (#88) (@​YingboMa)
• WIP: change to new @​muladd (#89) (@​devmotion)
• Add Nystrom5VelocityIndependent and fix Nystrom4VelocityIndependent (#95) (@​YingboMa)
• Updated @muladd and broadcasts (#104) (@​devmotion)
• LinearImplicitEuler (#109) (@​ChrisRackauckas)
• Remove integrator utils inlining (#121) (@​ChrisRackauckas)
• Fix DEDataArray (#124) (@​devmotion)
• Update tableaus and calculation of error estimates in low order RK methods (#128) (@​devmotion)
• Update tableaus and error estimate calculation of Verner RK methods (#129) (@​devmotion)
• Add forth order improved Runge-Kutta-Nyström method (#131) (@​YingboMa)
• Update Rosenbrock methods and explicit RK (#137) (@​devmotion)
• Update composite integrator and Feagin RK, exponential RK, low order RK, and Verner RK methods (#140) (@​devmotion)
• Update high order RK and threaded DP5 method (#142) (@​devmotion)
• Use Horner's rule in Tsit5 interpolants (#149) (@​devmotion)
• Add IRKN3 and tableaus for DPRKN6 (#150) (@​YingboMa)
• RK Nyström clean up (#154) (@​YingboMa)
• [WIP] Add DPRKN6 a.k.a. RKN6(4)6FD algorithm (#156) (@​YingboMa)
• Generalized Strang splitting (#157) (@​jagot)

... (truncated)

Changelog

Sourced from OrdinaryDiffEq's changelog.

OrdinaryDiffEq.jl v7 / DifferentialEquations.jl v8 Breaking Changes

This release bumps to SciMLBase v3, RecursiveArrayTools v4, and includes breaking changes across DiffEqBase, OrdinaryDiffEqCore, and all solver sublibraries. It also coincides with the DifferentialEquations.jl v8 umbrella release, which is itself a breaking change to the user-facing meta-package.

DifferentialEquations.jl v8: scope reduction

DifferentialEquations.jl v8 no longer re-exports the full SciML solver suite. Previously, using DifferentialEquations pulled in OrdinaryDiffEq, StochasticDiffEq, DelayDiffEq, BoundaryValueDiffEq, Sundials, JumpProcesses, SteadyStateDiffEq, LinearSolve, NonlinearSolve, Optimization, etc. — a large default surface that drove up using time and made it unclear which package any given solver actually came from.

In v8, using DifferentialEquations only loads OrdinaryDiffEq. All other solver families have been removed from the umbrella. If your code relied on DifferentialEquations for SDEs, DDEs, BVPs, jumps, steady states, or any non-ODE solver, you will need to add the topic-specific package to your project explicitly.

Migration

Find the topic you need a solver for and add the corresponding sublib(s) directly. The DiffEqDocs tutorials and solver pages now specify, per algorithm, which package it ships from. Common cases:

Topic	Old (DiffEq v7 umbrella)	New (DiffEq v8)
ODEs	using DifferentialEquations	using OrdinaryDiffEq (or using OrdinaryDiffEqTsit5, OrdinaryDiffEqRosenbrock, … for individual solver families)
Stochastic ODEs	using DifferentialEquations	using StochasticDiffEq
Delay ODEs	using DifferentialEquations	using DelayDiffEq
Boundary value problems	using DifferentialEquations	using BoundaryValueDiffEq (or one of BoundaryValueDiffEqMIRK, BoundaryValueDiffEqFIRK, BoundaryValueDiffEqShooting, …)
Jump processes	using DifferentialEquations	using JumpProcesses
Steady state	using DifferentialEquations	using SteadyStateDiffEq
DAEs (mass matrix or implicit)	using DifferentialEquations	using OrdinaryDiffEq (mass matrix), using Sundials (IDA), or topic sublib
Sundials wrappers (CVODE, IDA, ARKODE)	using DifferentialEquations	using Sundials
Linear / nonlinear / optimization	using DifferentialEquations	using LinearSolve / using NonlinearSolve / using Optimization

For ODE work specifically, prefer importing only the sublib you need (e.g. using OrdinaryDiffEqTsit5: Tsit5) rather than the umbrella using OrdinaryDiffEq — the v7 ecosystem split lets you trim using time substantially. The DiffEqDocs tutorials and solver index annotate every algorithm with its host sublib.

Why

Removing the meta-package's broad re-exports lets each topic's package version cycle independently, eliminates the long using DifferentialEquations precompile chain for users who only need ODEs, and makes the dependency graph for any given script honest about what's actually being loaded.

This change is independent of the OrdinaryDiffEq v7 changes below — OrdinaryDiffEq v7 ships with DifferentialEquations v8, but you can also use OrdinaryDiffEq v7 directly without the umbrella package at all.

OrdinaryDiffEq.jl v7 Breaking Changes

This release bumps to SciMLBase v3, RecursiveArrayTools v4, and includes breaking changes across DiffEqBase, OrdinaryDiffEqCore, and all solver sublibraries.

Themes of the v7 release

Most of the breaking changes fall into a small set of recurring themes. Keep these in mind while reading the migration table — they explain why an individual change exists and often suggest the right migration direction:

• Time to first solve (TTFS) reduction. Direct deps on Static.jl, StaticArrayInterface.jl, Polyester.jl, and StaticArrays.jl were dropped; using OrdinaryDiffEq now loads only the default solver set; ODEFunction switched to AutoSpecialize. All of this means less code loaded and more precompilation caching on first solve.
• Type stability everywhere. All Bool solver/solve keyword arguments (autodiff, verbose, alias, lazy, …) were replaced by typed objects. Passing a Bool no longer changes dispatch in ways the compiler cannot specialize on, and the reverse is no longer allowed to silently fall back through slow generic paths.
• Generality beyond ForwardDiff. chunk_size, diff_type, standardtag, etc. encoded ForwardDiff-specific or FiniteDiff-specific knobs on every solver. They are replaced by the ADTypes interface (AutoForwardDiff, AutoFiniteDiff, AutoEnzyme, AutoZygote, …) so every solver automatically generalizes to any AD backend.
• Controller is now an object, not a pile of solve kwargs. gamma, beta1, beta2, qmin, qmax, qsteady_min, qsteady_max, qoldinit were moved onto concrete PIController / PIDController / IController / PredictiveController structs, and EEst moved to the controller cache. This is prep work for pluggable controllers and removes a large amount of dead state from the integrator struct.
• Cleanup of old re-exports / deprecations. Functions like has_destats (now has_stats), sol.destats (now sol.stats), DEAlgorithm/DEProblem/DESolution abstract types, tuples()/intervals(), QuadratureProblem, fastpow, concrete_solve, etc. were on a deprecation path for one or more minor releases. v7 removes them.

Recommended upgrade path

... (truncated)

Commits

• f3ce496 Merge pull request #3567 from SciML/drop-unused-rosenbrock-tableaus-dep
• 02763e7 Drop unused OrdinaryDiffEqRosenbrockTableaus from top-level deps
• a0a61e0 Update version to 7.0.0 in Project.toml
• 68c304d Merge pull request #3566 from SciML/fix-delaydiffeq-extras-uuids
• 7c87e5a Fix three wrong UUIDs in DelayDiffEq's [extras]
• b3359fb Merge pull request #3565 from SciML/revert-core-ddt-bumps
• cfb94cd Revert OrdinaryDiffEqCore and DiffEqDevTools major bumps from #3562
• 5b867b8 Merge pull request #3563 from ChrisRackauckas-Claude/drop-old-majors-v7-stack
• a8419de Revert out-of-scope deps additions in Rosenbrock/Tsit5 QA test envs
• 260775b Drop old majors from v7-coupled stack compat
• Additional commits viewable in compare view

Note
Automatic rebases have been disabled on this pull request as it has been open for over 30 days.