up

Author: vyudu

src/systems/discrete_system/discrete_system.jl

@@ -17,7 +17,7 @@ eqs = [x(k+1) ~ σ*(y-x),
 @named de = DiscreteSystem(eqs)
 ```
 """
-struct DiscreteSystem <: AbstractDiscreteSystem
+struct DiscreteSystem <: AbstractTimeDependentSystem
     """
     A tag for the system. If two systems have the same tag, then they are
     structurally identical.
@@ -233,7 +233,6 @@ function DiscreteSystem(eqs, iv; kwargs...)
             push!(new_ps, p)
         end
     end
-    @show allunknowns
     return DiscreteSystem(eqs, iv,
         collect(allunknowns), collect(new_ps); kwargs...)
 end

src/systems/systems.jl

@@ -39,13 +39,13 @@ function structural_simplify(
     else
         newsys = newsys′
     end
-    # if newsys isa DiscreteSystem &&
-    #    any(eq -> symbolic_type(eq.lhs) == NotSymbolic(), equations(newsys))
-    #     error("""
-    #         Encountered algebraic equations when simplifying discrete system. This is \
-    #         not yet supported.
-    #     """)
-    # end
+    if newsys isa DiscreteSystem &&
+       any(eq -> symbolic_type(eq.lhs) == NotSymbolic(), equations(newsys))
+        error("""
+            Encountered algebraic equations when simplifying discrete system. This is \
+            not yet supported.
+        """)
+    end
     for pass in additional_passes
         newsys = pass(newsys)
     end

src/systems/systemstructure.jl

@@ -430,9 +430,9 @@ function TearingState(sys; quick_cancel = false, check = true)
 
     ts = TearingState(sys, fullvars,
         SystemStructure(complete(var_to_diff), complete(eq_to_diff),
-                        complete(graph), nothing, var_types, sys isa AbstractDiscreteSystem),
+            complete(graph), nothing, var_types, sys isa DiscreteSystem),
         Any[])
-    if sys isa AbstractDiscreteSystem 
+    if sys isa DiscreteSystem
         ts = shift_discrete_system(ts)
     end
     return ts
@@ -456,8 +456,6 @@ function lower_order_var(dervar, t)
     diffvar
 end
 
-"""
-"""
 function shift_discrete_system(ts::TearingState)
     @unpack fullvars, sys = ts
     discvars = OrderedSet()