Merge pull request #786 from AayushSabharwal/as/mtkv10

refactor: update to ModelingToolkitv10

Author: ChrisRackauckas

docs/Project.toml

@@ -60,7 +60,7 @@ FiniteDiff = "2"
 ForwardDiff = "0.10, 1"
 IncompleteLU = "0.2"
 JLD2 = "0.4, 0.5.1"
-ModelingToolkit = "9"
+ModelingToolkit = "10"
 NonlinearSolve = "3.15, 4"
 ODEProblemLibrary = "0.1"
 Optimization = "3, 4"

docs/src/basics/faq.md

@@ -194,8 +194,7 @@ DAE solvers will not be able to accurately solve the equation without rewriting
 ModelingToolkit is able to automatically detect this kind of condition and perform the equation
 transformation automatically. As such, if you are having difficulties with a DAE system, it is
 highly recommended to try `modelingtookitize` to transform the system to MTK's formulation and
-running `structural_simplify` to see how it would change the equations, simply convert the model
-to MTK.
+running `mtkcompile` to see how it would change the equations, simply convert the model to MTK.
 
 ## [Performance](@id faq_performance)
 

docs/src/examples/outer_solar_system.md

@@ -16,6 +16,7 @@ The data is taken from the book “Geometric Numerical Integration” by E. Hair
 
 ```@example outersolarsystem
 using Plots, OrdinaryDiffEq, ModelingToolkit
+using ModelingToolkit: t_nounits as t, D_nounits as D
 gr()
 
 G = 2.95912208286e-4
@@ -47,9 +48,8 @@ Here, we want to solve for the motion of the five outer planets relative to the
 ```@example outersolarsystem
 const ∑ = sum
 const N = 6
-@variables t u(t)[1:3, 1:N]
+@variables u(t)[1:3, 1:N]
 u = collect(u)
-D = Differential(t)
 potential = -G *
             ∑(
     i -> ∑(j -> (M[i] * M[j]) / √(∑(k -> (u[k, i] - u[k, j])^2, 1:3)), 1:(i - 1)),
@@ -71,8 +71,7 @@ Thus, $\dot{q}$ is defined by the masses. We only need to define $\dot{p}$, and
 ```@example outersolarsystem
 eqs = vec(@. D(D(u))) .~ .-ModelingToolkit.gradient(potential, vec(u)) ./
                          repeat(M, inner = 3)
-@named sys = ODESystem(eqs, t)
-ss = structural_simplify(sys)
+@mtkcompile sys = System(eqs, t)
 prob = ODEProblem(ss, [vec(u .=> pos); vec(D.(u) .=> vel)], tspan)
 sol = solve(prob, Tsit5());
 ```