Don't check units during initialization

...because initialization problems don't correctly handle units and units have already been checked during system initialization.

Author: ctessum

src/systems/diffeqs/abstractodesystem.jl

@@ -851,7 +851,7 @@ function process_DEProblem(constructor, sys::AbstractODESystem, u0map, parammap;
         build_initializeprob = true,
         initialization_eqs = [],
         fully_determined = false,
-        check_units = true,
+        check_units = false,
         kwargs...)
     eqs = equations(sys)
     dvs = unknowns(sys)
@@ -916,7 +916,8 @@ function process_DEProblem(constructor, sys::AbstractODESystem, u0map, parammap;
 
         initializeprob = ModelingToolkit.InitializationProblem(
             sys, t, u0map, parammap; guesses, warn_initialize_determined,
-            initialization_eqs, eval_expression, eval_module, fully_determined, check_units)
+            initialization_eqs, eval_expression, eval_module, fully_determined,
+            check_units = check_units)
         initializeprobmap = getu(initializeprob, unknowns(sys))
         punknowns = [p
                      for p in all_variable_symbols(initializeprob) if is_parameter(sys, p)]

test/initializationsystem.jl

@@ -3,6 +3,7 @@ using ForwardDiff
 using SymbolicIndexingInterface, SciMLStructures
 using SciMLStructures: Tunable
 using ModelingToolkit: t_nounits as t, D_nounits as D
+using DynamicQuantities
 
 @parameters g
 @variables x(t) y(t) [state_priority = 10] λ(t)
@@ -814,3 +815,19 @@ end
     prob2 = @test_nowarn remake(prob; u0 = [y => 0.5])
     @test is_variable(prob.f.initializeprob, p)
 end
+
+@testset "units" begin
+    t = ModelingToolkit.t
+    D = ModelingToolkit.D
+    @parameters g [unit = u"m/s^2"] L=1 [unit = u"m^2"]
+    @variables x(t) [unit = u"m"] y(t) [unit = u"m" state_priority = 10] λ(t) [unit = u"s^-2"]
+    eqs = [D(D(x)) ~ λ * x
+           D(D(y)) ~ λ * y - g
+           x^2 + y^2 ~ L]
+    @mtkbuild pend = ODESystem(eqs, t)
+
+    prob = ODEProblem(pend, [x => 1, y => 0], (0.0, 1.5), [g => 1],
+        guesses = ModelingToolkit.missing_variable_defaults(pend))
+    sol = solve(prob, Rodas5P())
+    @test SciMLBase.successful_retcode(sol)
+end