Merge pull request #289 from BambOoxX/main

Fix `states` -> `unknowns`

Author: ChrisRackauckas

src/Blocks/analysis_points.jl

@@ -23,7 +23,7 @@ function ap_var(sys)
         # collect to turn symbolic arrays into arrays of symbols
         return length(sys.u) == 1 ? sys.u : collect(sys.u)
     end
-    x = states(sys)
+    x = unknowns(sys)
     length(x) == 1 && return x[1]
     error("Could not determine the analysis-point variable in system $(nameof(sys)). To use an analysis point, apply it to a connection between two causal blocks containing connectors of type `RealInput/RealOutput` from ModelingToolkitStandardLibrary.Blocks.")
 end

test/Mechanical/multibody.jl

@@ -22,11 +22,11 @@ eqs = [connect(link1.TX1, cart.flange) #, force.flange)
 @named model = ODESystem(eqs, t, [], []; systems = [link1, link2, cart, fixed])
 
 sys = structural_simplify(model)
-@test length(states(sys)) == 6
+@test length(unknowns(sys)) == 6
 
 # The below code does work...
 #=
-unset_vars = setdiff(states(sys), keys(ModelingToolkit.defaults(sys)))
+unset_vars = setdiff(unknowns(sys), keys(ModelingToolkit.defaults(sys)))
 prob = ODEProblem(sys, unset_vars .=> 0.0, (0.0, 20), []; jac = true)
 sol = solve(prob, Rodas5P())
 
@@ -44,7 +44,7 @@ f
 
 function plot_link(sol, sys, tmax)
     tm = Observable(0.0)
-    idx = Dict(reverse.(enumerate(states(sys))))
+    idx = Dict(reverse.(enumerate(unknowns(sys))))
 
     fig = Figure()
     a = Axis(fig[1,1], aspect=DataAspect(), )