fix: handle symbolic values for parameters passed to linearize

Author: AayushSabharwal

src/linearization.jl

@@ -590,9 +590,12 @@ function linearize(sys, lin_fun::LinearizationFunction; t = 0.0,
         p = DiffEqBase.NullParameters())
     prob = LinearizationProblem(lin_fun, t)
     op = anydict(op)
-    evaluate_varmap!(op, unknowns(sys))
+    evaluate_varmap!(op, keys(op))
     for (k, v) in op
         v === nothing && continue
+        if symbolic_type(v) != NotSymbolic() || is_array_of_symbolics(v)
+            v = getu(prob, v)(prob)
+        end
         if is_parameter(prob, Initial(k))
             setu(prob, Initial(k))(prob, v)
         else

test/downstream/linearize.jl

@@ -329,3 +329,11 @@ end
         sys, [x], []; op = Dict(x => 1.0), guesses = Dict(y => 1.0),
         allow_input_derivatives = true)
 end
+
+@testset "Symbolic values for parameters in `linearize`" begin
+    @named tank_noi = Tank_noi()
+    @unpack md_i, h, m, ρ, A, K = tank_noi
+    m_ss = 2.4000000003229878
+    @test_nowarn linearize(
+        tank_noi, [md_i], [h]; op = Dict(m => m_ss, md_i => 2, ρ => A / K, A => 5))
+end