refactor: move HomtopyContinuation-related code to its own file

Author: AayushSabharwal

src/ModelingToolkit.jl

@@ -149,6 +149,7 @@ include("systems/callbacks.jl")
 include("systems/problem_utils.jl")
 
 include("systems/nonlinear/nonlinearsystem.jl")
+include("systems/nonlinear/homotopy_continuation.jl")
 include("systems/diffeqs/odesystem.jl")
 include("systems/diffeqs/sdesystem.jl")
 include("systems/diffeqs/abstractodesystem.jl")

src/systems/nonlinear/homotopy_continuation.jl

@@ -0,0 +1,68 @@
+"""
+$(TYPEDEF)
+
+A type of Nonlinear problem which specializes on polynomial systems and uses
+HomotopyContinuation.jl to solve the system. Requires importing HomotopyContinuation.jl to
+create and solve.
+"""
+struct HomotopyContinuationProblem{uType, H, D, O, SS, U} <:
+       SciMLBase.AbstractNonlinearProblem{uType, true}
+    """
+    The initial values of states in the system. If there are multiple real roots of
+    the system, the one closest to this point is returned.
+    """
+    u0::uType
+    """
+    A subtype of `HomotopyContinuation.AbstractSystem` to solve. Also contains the
+    parameter object.
+    """
+    homotopy_continuation_system::H
+    """
+    A function with signature `(u, p) -> resid`. In case of rational functions, this
+    is used to rule out roots of the system which would cause the denominator to be
+    zero.
+    """
+    denominator::D
+    """
+    The `NonlinearSystem` used to create this problem. Used for symbolic indexing.
+    """
+    sys::NonlinearSystem
+    """
+    A function which generates and returns observed expressions for the given system.
+    """
+    obsfn::O
+    """
+    The HomotopyContinuation.jl solver and start system, obtained through
+    `HomotopyContinuation.solver_startsystems`.
+    """
+    solver_and_starts::SS
+    """
+    A function which takes a solution of the transformed system, and returns a vector
+    of solutions for the original system. This is utilized when converting systems
+    to polynomials.
+    """
+    unpack_solution::U
+end
+
+function HomotopyContinuationProblem(::AbstractSystem, _u0, _p; kwargs...)
+    error("HomotopyContinuation.jl is required to create and solve `HomotopyContinuationProblem`s. Please run `Pkg.add(\"HomotopyContinuation\")` to continue.")
+end
+
+SymbolicIndexingInterface.symbolic_container(p::HomotopyContinuationProblem) = p.sys
+SymbolicIndexingInterface.state_values(p::HomotopyContinuationProblem) = p.u0
+function SymbolicIndexingInterface.set_state!(p::HomotopyContinuationProblem, args...)
+    set_state!(p.u0, args...)
+end
+function SymbolicIndexingInterface.parameter_values(p::HomotopyContinuationProblem)
+    parameter_values(p.homotopy_continuation_system)
+end
+function SymbolicIndexingInterface.set_parameter!(p::HomotopyContinuationProblem, args...)
+    set_parameter!(parameter_values(p), args...)
+end
+function SymbolicIndexingInterface.observed(p::HomotopyContinuationProblem, sym)
+    if p.obsfn !== nothing
+        return p.obsfn(sym)
+    else
+        return SymbolicIndexingInterface.observed(p.sys, sym)
+    end
+end

src/systems/nonlinear/nonlinearsystem.jl

@@ -682,72 +682,3 @@ function Base.:(==)(sys1::NonlinearSystem, sys2::NonlinearSystem)
         _eq_unordered(get_ps(sys1), get_ps(sys2)) &&
         all(s1 == s2 for (s1, s2) in zip(get_systems(sys1), get_systems(sys2)))
 end
-
-"""
-$(TYPEDEF)
-
-A type of Nonlinear problem which specializes on polynomial systems and uses
-HomotopyContinuation.jl to solve the system. Requires importing HomotopyContinuation.jl to
-create and solve.
-"""
-struct HomotopyContinuationProblem{uType, H, D, O, SS, U} <:
-       SciMLBase.AbstractNonlinearProblem{uType, true}
-    """
-    The initial values of states in the system. If there are multiple real roots of
-    the system, the one closest to this point is returned.
-    """
-    u0::uType
-    """
-    A subtype of `HomotopyContinuation.AbstractSystem` to solve. Also contains the
-    parameter object.
-    """
-    homotopy_continuation_system::H
-    """
-    A function with signature `(u, p) -> resid`. In case of rational functions, this
-    is used to rule out roots of the system which would cause the denominator to be
-    zero.
-    """
-    denominator::D
-    """
-    The `NonlinearSystem` used to create this problem. Used for symbolic indexing.
-    """
-    sys::NonlinearSystem
-    """
-    A function which generates and returns observed expressions for the given system.
-    """
-    obsfn::O
-    """
-    The HomotopyContinuation.jl solver and start system, obtained through
-    `HomotopyContinuation.solver_startsystems`.
-    """
-    solver_and_starts::SS
-    """
-    A function which takes a solution of the transformed system, and returns a vector
-    of solutions for the original system. This is utilized when converting systems
-    to polynomials.
-    """
-    unpack_solution::U
-end
-
-function HomotopyContinuationProblem(::AbstractSystem, _u0, _p; kwargs...)
-    error("HomotopyContinuation.jl is required to create and solve `HomotopyContinuationProblem`s. Please run `Pkg.add(\"HomotopyContinuation\")` to continue.")
-end
-
-SymbolicIndexingInterface.symbolic_container(p::HomotopyContinuationProblem) = p.sys
-SymbolicIndexingInterface.state_values(p::HomotopyContinuationProblem) = p.u0
-function SymbolicIndexingInterface.set_state!(p::HomotopyContinuationProblem, args...)
-    set_state!(p.u0, args...)
-end
-function SymbolicIndexingInterface.parameter_values(p::HomotopyContinuationProblem)
-    parameter_values(p.homotopy_continuation_system)
-end
-function SymbolicIndexingInterface.set_parameter!(p::HomotopyContinuationProblem, args...)
-    set_parameter!(parameter_values(p), args...)
-end
-function SymbolicIndexingInterface.observed(p::HomotopyContinuationProblem, sym)
-    if p.obsfn !== nothing
-        return p.obsfn(sym)
-    else
-        return SymbolicIndexingInterface.observed(p.sys, sym)
-    end
-end