add option to access state bounds

Author: baggepinnen

src/variables.jl

@@ -237,16 +237,17 @@ function tunable_parameters(sys, p = parameters(sys); default = false)
 end
 
 """
-    getbounds(sys::ModelingToolkit.AbstractSystem)
+    getbounds(sys::ModelingToolkit.AbstractSystem, p = parameters(sys))
 
 Returns a dict with pairs `p => (lb, ub)` mapping parameters of `sys` to lower and upper bounds.
 Create parameters with bounds like this
 ```
 @parameters p [bounds=(-1, 1)]
 ```
+
+To obtain state bounds, call `getbounds(sys, states(sys))`
 """
-function getbounds(sys::ModelingToolkit.AbstractSystem)
-    p = parameters(sys)
+function getbounds(sys::ModelingToolkit.AbstractSystem, p = parameters(sys))
     Dict(p .=> getbounds.(p))
 end
 

test/test_variable_metadata.jl

@@ -35,7 +35,7 @@ d = FakeNormal()
 ## System interface
 @parameters t
 Dₜ = Differential(t)
-@variables x(t)=0 u(t)=0 [input = true] y(t)=0 [output = true]
+@variables x(t)=0 [bounds = (-10, 10)] u(t)=0 [input = true] y(t)=0 [output = true]
 @parameters T [tunable = true, bounds = (0, Inf)]
 @parameters k [tunable = true, bounds = (0, Inf)]
 @parameters k2
@@ -57,6 +57,9 @@ lb, ub = getbounds(p)
 b = getbounds(sys)
 @test b[T] == (0, Inf)
 
+b = getbounds(sys, states(sys))
+@test b[x] == (-10, 10)
+
 p = tunable_parameters(sys, default = true)
 sp = Set(p)
 @test k ∈ sp