fix: require simplification again

Author: vyudu

src/linearization.jl

@@ -46,7 +46,7 @@ function linearization_function(sys::AbstractSystem, inputs = inputs(sys),
         warn_empty_op = true,
         kwargs...)
     if !iscomplete(sys)
-        sys = structural_simplify(sys; inputs, outputs)
+        error("A simplified `ODESystem` is required. Call `structural_simplify` on the system with the inputs and outputs before creating the linearization function.")
     end
     op = Dict(op)
     if isempty(op) && warn_empty_op

src/systems/analysis_points.jl

@@ -928,8 +928,7 @@ function open_loop(sys, ap::Union{Symbol, AnalysisPoint}; system_modifier = iden
     return system_modifier(sys), vars
 end
 
-function linearization_function(sys::AbstractSystem,
-        inputs::Union{Symbol, Vector{Symbol}, AnalysisPoint, Vector{AnalysisPoint}},
+function ap_preprocessing(sys::AbstractSystem, inputs::Union{Symbol, Vector{Symbol}, AnalysisPoint, Vector{AnalysisPoint}},
         outputs; loop_openings = [], system_modifier = identity, kwargs...)
     loop_openings = Set(map(nameof, canonicalize_ap(sys, loop_openings)))
     inputs = canonicalize_ap(sys, inputs)
@@ -958,7 +957,13 @@ function linearization_function(sys::AbstractSystem,
     end
 
     sys = handle_loop_openings(sys, map(AnalysisPoint, collect(loop_openings)))
+    sys, input_vars, output_vars
+end
 
+function linearization_function(sys::AbstractSystem,
+        inputs::Union{Symbol, Vector{Symbol}, AnalysisPoint, Vector{AnalysisPoint}},
+        outputs; loop_openings = [], system_modifier = identity, kwargs...)
+    sys, inputs, outputs = ap_preprocessing(sys; inputs, outputs, loop_openings, system_modifier, kwargs...)
     return linearization_function(system_modifier(sys), input_vars, output_vars; kwargs...)
 end
 

src/systems/systems.jl

@@ -32,6 +32,10 @@ function structural_simplify(
         disturbance_inputs = Any[],
         kwargs...)
     isscheduled(sys) && throw(RepeatedStructuralSimplificationError())
+    if inputs isa Union{Symbol, Vector{Symbol}, AnalysisPoint, Vector{AnalysisPoint}}
+        sys, inputs, outputs = ap_preprocessing(sys, inputs, outputs, kwargs...)
+    end
+
     newsys′ = __structural_simplification(sys; simplify,
         allow_symbolic, allow_parameter, conservative, fully_determined,
         inputs, outputs, disturbance_inputs,

test/downstream/linearize.jl

@@ -33,7 +33,7 @@ lsys = linearize(sys2)
 @test lsys.C[] == 0
 @test lsys.D[] == 1
 
-lsys = linearize(sys, r, r) # Test allow scalars
+lsys = linearize(sys2, r, r) # Test allow scalars
 
 @test lsys.A[] == -2
 @test lsys.B[] == 1
@@ -269,7 +269,8 @@ closed_loop = ODESystem(connections, t, systems = [model, pid, filt, sensor, r,
         filt.xd => 0.0
     ])
 
-@test_nowarn linearize(closed_loop, :r, :y; warn_empty_op = false)
+closed_loop = structural_simplify(closed_loop, inputs = :r, outputs = :y)
+linearize(closed_loop; warn_empty_op = false)
 
 # https://discourse.julialang.org/t/mtk-change-in-linearize/115760/3
 @mtkmodel Tank_noi begin
@@ -299,6 +300,7 @@ end
 
 @named tank_noi = Tank_noi()
 @unpack md_i, h, m = tank_noi
+tank_noi = structural_simplify(tank_noi, inputs = [md_i], outputs = [h])
 m_ss = 2.4000000003229878
 @test_nowarn linearize(tank_noi, [md_i], [h]; op = Dict(m => m_ss, md_i => 2))
 
@@ -307,6 +309,7 @@ m_ss = 2.4000000003229878
 @parameters p = 1.0
 eqs = [D(x) ~ p * u, x ~ y]
 @named sys = ODESystem(eqs, t)
+sys = structural_simplify(sys, inputs = [u])
 
 matrices1 = linearize(sys, [u], []; op = Dict(x => 2.0))
 matrices2 = linearize(sys, [u], []; op = Dict(y => 2.0))