build_function from ODESystem

Author: ChrisRackauckas

Project.toml

@@ -1,7 +1,7 @@
 name = "ModelingToolkit"
 uuid = "961ee093-0014-501f-94e3-6117800e7a78"
 authors = ["Chris Rackauckas <accounts@chrisrackauckas.com>"]
-version = "1.4.1"
+version = "1.4.2"
 
 [deps]
 DiffEqBase = "2b5f629d-d688-5b77-993f-72d75c75574e"

src/build_function.jl

@@ -92,6 +92,9 @@ function _build_function(target::JuliaTarget, rhss, vs, ps = (), args = (),
     end
 end
 
+get_varnumber(varop::Operation,vars::Vector{Operation}) =  findfirst(x->isequal(x,varop),vars)
+get_varnumber(varop::Operation,vars::Vector{Variable})  =  findfirst(x->isequal(x,varop.op),vars)
+
 function numbered_expr(O::Equation,args...;kwargs...)
   :($(numbered_expr(O.lhs,args...;kwargs...)) = $(numbered_expr(O.rhs,args...;kwargs...)))
 end
@@ -101,12 +104,12 @@ function numbered_expr(O::Operation,vars,parameters;
                        varname=:u,paramname=:p)
   if isa(O.op, ModelingToolkit.Differential)
     varop = O.args[1]
-    i = findfirst(x->isequal(x,varop),vars)
+    i = get_varnumber(varop,vars)
     return :($derivname[$i])
   elseif isa(O.op, ModelingToolkit.Variable)
-    i = findfirst(x->isequal(x,O),vars)
+    i = get_varnumber(O,vars)
     if i == nothing
-      i = findfirst(x->isequal(x,O),parameters)
+      i = get_varnumber(O,parameters)
       return :($paramname[$i])
     else
       return :($varname[$i])
@@ -116,7 +119,15 @@ function numbered_expr(O::Operation,vars,parameters;
          [numbered_expr(x,vars,parameters;derivname=derivname,
                         varname=varname,paramname=paramname) for x in O.args]...)
 end
-function numbered_expr(de::ModelingToolkit.DiffEq,vars,parameters;
+
+function numbered_expr(de::ModelingToolkit.DiffEq,vars::Vector{Variable},parameters;
+                       derivname=:du,varname=:u,paramname=:p)
+    i = findfirst(x->isequal(x.name,de.x.name),vars)
+    :($derivname[$i] = $(numbered_expr(de.rhs,vars,parameters;
+                                     derivname=derivname,
+                                     varname=varname,paramname=paramname)))
+end
+function numbered_expr(de::ModelingToolkit.DiffEq,vars::Vector{Operation},parameters;
                        derivname=:du,varname=:u,paramname=:p)
     i = findfirst(x->isequal(x.op.name,de.x.name),vars)
     :($derivname[$i] = $(numbered_expr(de.rhs,vars,parameters;

src/systems/diffeqs/diffeqsystem.jl

@@ -289,9 +289,12 @@ $(SIGNATURES)
 Generate `ODESystem`, dependent variables, and parameters from an `ODEProblem`.
 """
 function modelingtoolkitize(prob::DiffEqBase.ODEProblem)
+    prob.f isa DiffEqBase.AbstractParameterizedFunction &&
+                            return (prob.f.sys, prob.f.sys.dvs, prob.f.sys.ps)
     @parameters t
     vars = [Variable(:x, i)(t) for i in eachindex(prob.u0)]
-    params = [Variable(:α,i; known = true)() for i in eachindex(prob.p)]
+    params = prob.p isa DiffEqBase.NullParameters ? [] :
+             [Variable(:α,i; known = true)() for i in eachindex(prob.p)]
     @derivatives D'~t
 
     rhs = [D(var) for var in vars]

test/build_targets.jl

@@ -36,3 +36,12 @@ sys = ODESystem(eqs,t,[x,y],[a])
 
 @test ModelingToolkit.build_function(eqs,[x,y],[a],t,target = ModelingToolkit.MATLABTarget()) ==
       ModelingToolkit.build_function(sys.eqs,[x,y],[a],t,target = ModelingToolkit.MATLABTarget())
+
+@test ModelingToolkit.build_function(eqs,[x,y],[a],t,target = ModelingToolkit.CTarget()) ==
+      ModelingToolkit.build_function(sys.eqs,sys.dvs,sys.ps,sys.iv,target = ModelingToolkit.CTarget())
+
+@test ModelingToolkit.build_function(eqs,[x,y],[a],t,target = ModelingToolkit.StanTarget()) ==
+      ModelingToolkit.build_function(sys.eqs,sys.dvs,sys.ps,sys.iv,target = ModelingToolkit.StanTarget())
+
+@test ModelingToolkit.build_function(eqs,[x,y],[a],t,target = ModelingToolkit.MATLABTarget()) ==
+      ModelingToolkit.build_function(sys.eqs,sys.dvs,sys.ps,sys.iv,target = ModelingToolkit.MATLABTarget())