SciML · avik-pal · Mar 17, 2025 · Mar 17, 2025 · Mar 18, 2025 · Mar 18, 2025
diff --git a/Project.toml b/Project.toml
@@ -42,6 +42,8 @@ SimpleNonlinearSolve = {path = "lib/SimpleNonlinearSolve"}
 [weakdeps]
 FastLevenbergMarquardt = "7a0df574-e128-4d35-8cbd-3d84502bf7ce"
 FixedPointAcceleration = "817d07cb-a79a-5c30-9a31-890123675176"
+Gridap = "56d4f2e9-7ea1-5844-9cf6-b9c51ca7ce8e"
+GridapPETSc = "bcdc36c2-0c3e-11ea-095a-c9dadae499f1"
 LeastSquaresOptim = "0fc2ff8b-aaa3-5acd-a817-1944a5e08891"
 LineSearches = "d3d80556-e9d4-5f37-9878-2ab0fcc64255"
 MINPACK = "4854310b-de5a-5eb6-a2a5-c1dee2bd17f9"
@@ -53,9 +55,16 @@ SIAMFANLEquations = "084e46ad-d928-497d-ad5e-07fa361a48c4"
 SpeedMapping = "f1835b91-879b-4a3f-a438-e4baacf14412"
 Sundials = "c3572dad-4567-51f8-b174-8c6c989267f4"
 
+[sources]
+NonlinearSolveBase = {path = "lib/NonlinearSolveBase"}
+NonlinearSolveFirstOrder = {path = "lib/NonlinearSolveFirstOrder"}
+NonlinearSolveQuasiNewton = {path = "lib/NonlinearSolveQuasiNewton"}
+NonlinearSolveSpectralMethods = {path = "lib/NonlinearSolveSpectralMethods"}
+
 [extensions]
 NonlinearSolveFastLevenbergMarquardtExt = "FastLevenbergMarquardt"
 NonlinearSolveFixedPointAccelerationExt = "FixedPointAcceleration"
+NonlinearSolveGridapPETScExt = ["Gridap", "GridapPETSc"]
 NonlinearSolveLeastSquaresOptimExt = "LeastSquaresOptim"
 NonlinearSolveMINPACKExt = "MINPACK"
 NonlinearSolveNLSolversExt = "NLSolvers"

diff --git a/ext/NonlinearSolveGridapPETScExt.jl b/ext/NonlinearSolveGridapPETScExt.jl
@@ -0,0 +1,123 @@
+module NonlinearSolveGridapPETScExt
+
+using Gridap: Gridap, Algebra
+using GridapPETSc: GridapPETSc
+
+using NonlinearSolveBase: NonlinearSolveBase
+using NonlinearSolve: NonlinearSolve, GridapPETScSNES
+using SciMLBase: SciMLBase, NonlinearProblem, ReturnCode
+
+using ConcreteStructs: @concrete
+using FastClosures: @closure
+
+@concrete struct NonlinearSolveOperator <: Algebra.NonlinearOperator
+    f!
+    jac!
+    initial_guess_cache
+    resid_prototype
+    jacobian_prototype
+end
+
+function Algebra.residual!(b::AbstractVector, op::NonlinearSolveOperator, x::AbstractVector)
+    op.f!(b, x)
+end
+
+function Algebra.jacobian!(
+        A::AbstractMatrix, op::NonlinearSolveOperator, x::AbstractVector
+)
+    op.jac!(A, x)
+end
+
+function Algebra.zero_initial_guess(op::NonlinearSolveOperator)
+    fill!(op.initial_guess_cache, 0)
+    return op.initial_guess_cache
+end
+
+function Algebra.allocate_residual(op::NonlinearSolveOperator, ::AbstractVector)
+    fill!(op.resid_prototype, 0)
+    return op.resid_prototype
+end
+
+function Algebra.allocate_jacobian(op::NonlinearSolveOperator, ::AbstractVector)
+    fill!(op.jacobian_prototype, 0)
+    return op.jacobian_prototype
+end
+
+# TODO: Later we should just wrap `Gridap` generally and pass in `PETSc` as the solver
+function SciMLBase.__solve(
+        prob::NonlinearProblem, alg::GridapPETScSNES, args...;
+        abstol = nothing, reltol = nothing,
+        maxiters = 1000, alias_u0::Bool = false, termination_condition = nothing,
+        show_trace::Val = Val(false), kwargs...
+)
+    # XXX: https://petsc.org/release/manualpages/SNES/SNESSetConvergenceTest/
+    NonlinearSolveBase.assert_extension_supported_termination_condition(
+        termination_condition, alg; abs_norm_supported = false
+    )
+
+    f_wrapped!, u0, resid = NonlinearSolveBase.construct_extension_function_wrapper(
+        prob; alias_u0
+    )
+    T = eltype(u0)
+
+    abstol = NonlinearSolveBase.get_tolerance(abstol, T)
+    reltol = NonlinearSolveBase.get_tolerance(reltol, T)
+
+    nf = Ref{Int}(0)
+
+    f! = @closure (fx, x) -> begin
+        nf[] += 1
+        f_wrapped!(fx, x)
+        return fx
+    end
+
+    if prob.u0 isa Number
+        jac! = NonlinearSolveBase.construct_extension_jac(
+            prob, alg, prob.u0, prob.u0; alg.autodiff
+        )
+        J_init = zeros(T, 1, 1)
+    else
+        jac!, J_init = NonlinearSolveBase.construct_extension_jac(
+            prob, alg, u0, resid; alg.autodiff, initial_jacobian = Val(true)
+        )
+    end
+
+    njac = Ref{Int}(-1)
+    jac_fn! = @closure (J, x) -> begin
+        njac[] += 1
+        jac!(J, x)
+        return J
+    end
+
+    nop = NonlinearSolveOperator(f!, jac_fn!, u0, resid, J_init)
+
+    petsc_args = [
+        "-snes_rtol", string(reltol), "-snes_atol", string(abstol),
+        "-snes_max_it", string(maxiters)
+    ]
+    for (k, v) in pairs(alg.snes_options)
+        push!(petsc_args, "-$(k)")
+        push!(petsc_args, string(v))
+    end
+    show_trace isa Val{true} && push!(petsc_args, "-snes_monitor")
+
+    # TODO: We can reuse the cache returned from this function
+    sol_u = GridapPETSc.with(args = petsc_args) do
+        sol_u = copy(u0)
+        Algebra.solve!(sol_u, GridapPETSc.PETScNonlinearSolver(), nop)
+        return sol_u
+    end
+
+    f_wrapped!(resid, sol_u)
+    u_res = prob.u0 isa Number ? sol_u[1] : sol_u
+    resid_res = prob.u0 isa Number ? resid[1] : resid
+
+    objective = maximum(abs, resid)
+    retcode = ifelse(objective ≤ abstol, ReturnCode.Success, ReturnCode.Failure)
+    return SciMLBase.build_solution(
+        prob, alg, u_res, resid_res;
+        retcode, stats = SciMLBase.NLStats(nf[], njac[], -1, -1, -1)
+    )
+end
+
+end
-end
+end
-end
+end
diff --git a/ext/NonlinearSolvePETScExt.jl b/ext/NonlinearSolvePETScExt.jl
@@ -17,6 +17,11 @@ function SciMLBase.__solve(
         maxiters = 1000, alias_u0::Bool = false, termination_condition = nothing,
         show_trace::Val = Val(false), kwargs...
 )
+    if !MPI.Initialized()
+        @warn "MPI not initialized. Initializing MPI with MPI.Init()." maxlog=1
+        MPI.Init()
+    end
+
     # XXX: https://petsc.org/release/manualpages/SNES/SNESSetConvergenceTest/
     NonlinearSolveBase.assert_extension_supported_termination_condition(
         termination_condition, alg; abs_norm_supported = false
@@ -68,8 +73,10 @@ function SciMLBase.__solve(
     PETSc.setfunction!(snes, f!, PETSc.VecSeq(zero(u0)))
 
     njac = Ref{Int}(-1)
-    if alg.autodiff !== missing || prob.f.jac !== nothing
+    # `missing` -> let PETSc compute the Jacobian using finite differences
+    if alg.autodiff !== missing
         autodiff = alg.autodiff === missing ? nothing : alg.autodiff
+
         if prob.u0 isa Number
             jac! = NonlinearSolveBase.construct_extension_jac(
                 prob, alg, prob.u0, prob.u0; autodiff
@@ -125,8 +132,7 @@ function SciMLBase.__solve(
     retcode = ifelse(objective ≤ abstol, ReturnCode.Success, ReturnCode.Failure)
     return SciMLBase.build_solution(
         prob, alg, u_res, resid_res;
-        retcode, original = snes,
-        stats = SciMLBase.NLStats(nf[], njac[], -1, -1, -1)
+        retcode, stats = SciMLBase.NLStats(nf[], njac[], -1, -1, -1)
     )
 end
 

diff --git a/lib/BracketingNonlinearSolve/Project.toml b/lib/BracketingNonlinearSolve/Project.toml
@@ -45,3 +45,6 @@ TestItemRunner = "f8b46487-2199-4994-9208-9a1283c18c0a"
 
 [targets]
 test = ["Aqua", "ExplicitImports", "ForwardDiff", "InteractiveUtils", "Test", "TestItemRunner"]
+
+[sources]
+NonlinearSolveBase = {path = "../NonlinearSolveBase"}
diff --git a/lib/NonlinearSolveBase/Project.toml b/lib/NonlinearSolveBase/Project.toml
@@ -92,3 +92,6 @@ Test = "8dfed614-e22c-5e08-85e1-65c5234f0b40"
 
 [targets]
 test = ["Aqua", "BandedMatrices", "DiffEqBase", "ExplicitImports", "ForwardDiff", "InteractiveUtils", "LinearAlgebra", "SparseArrays", "Test"]
+
+[sources]
+SciMLJacobianOperators = {path = "../SciMLJacobianOperators"}
diff --git a/lib/NonlinearSolveFirstOrder/Project.toml b/lib/NonlinearSolveFirstOrder/Project.toml
@@ -91,3 +91,7 @@ Zygote = "e88e6eb3-aa80-5325-afca-941959d7151f"
 
 [targets]
 test = ["Aqua", "BandedMatrices", "BenchmarkTools", "ForwardDiff", "Enzyme", "ExplicitImports", "Hwloc", "InteractiveUtils", "LineSearch", "LineSearches", "NonlinearProblemLibrary", "Pkg", "Random", "ReTestItems", "SparseArrays", "SparseConnectivityTracer", "SparseMatrixColorings", "StableRNGs", "StaticArrays", "Test", "Zygote"]
+
+[sources]
+NonlinearSolveBase = {path = "../NonlinearSolveBase"}
+SciMLJacobianOperators = {path = "../SciMLJacobianOperators"}
diff --git a/lib/NonlinearSolveHomotopyContinuation/Project.toml b/lib/NonlinearSolveHomotopyContinuation/Project.toml
@@ -47,3 +47,6 @@ Test = "8dfed614-e22c-5e08-85e1-65c5234f0b40"
 
 [targets]
 test = ["Aqua", "Test", "NonlinearSolve", "Enzyme", "NaNMath"]
+
+[sources]
+NonlinearSolveBase = {path = "../NonlinearSolveBase"}
diff --git a/lib/NonlinearSolveQuasiNewton/Project.toml b/lib/NonlinearSolveQuasiNewton/Project.toml
@@ -83,3 +83,6 @@ Zygote = "e88e6eb3-aa80-5325-afca-941959d7151f"
 
 [targets]
 test = ["ADTypes", "Aqua", "BenchmarkTools", "Enzyme", "ExplicitImports", "FiniteDiff", "ForwardDiff", "Hwloc", "InteractiveUtils", "LineSearch", "LineSearches", "NonlinearProblemLibrary", "Pkg", "ReTestItems", "StableRNGs", "StaticArrays", "Test", "Zygote"]
+
+[sources]
+NonlinearSolveBase = {path = "../NonlinearSolveBase"}
diff --git a/lib/NonlinearSolveSpectralMethods/Project.toml b/lib/NonlinearSolveSpectralMethods/Project.toml
@@ -62,3 +62,6 @@ Test = "8dfed614-e22c-5e08-85e1-65c5234f0b40"
 
 [targets]
 test = ["Aqua", "BenchmarkTools", "ExplicitImports", "Hwloc", "InteractiveUtils", "NonlinearProblemLibrary", "Pkg", "ReTestItems", "StableRNGs", "StaticArrays", "Test"]
+
+[sources]
+NonlinearSolveBase = {path = "../NonlinearSolveBase"}
diff --git a/lib/SCCNonlinearSolve/Project.toml b/lib/SCCNonlinearSolve/Project.toml
@@ -48,3 +48,6 @@ Test = "8dfed614-e22c-5e08-85e1-65c5234f0b40"
 
 [targets]
 test = ["Aqua", "BenchmarkTools", "ExplicitImports", "Hwloc", "InteractiveUtils", "NonlinearProblemLibrary", "NonlinearSolveBase", "NonlinearSolveFirstOrder", "Pkg", "ReTestItems", "StableRNGs", "StaticArrays", "Test"]
+
+[sources]
+NonlinearSolveFirstOrder = {path = "../NonlinearSolveFirstOrder"}
diff --git a/lib/SimpleNonlinearSolve/Project.toml b/lib/SimpleNonlinearSolve/Project.toml
@@ -95,3 +95,6 @@ Zygote = "e88e6eb3-aa80-5325-afca-941959d7151f"
 
 [targets]
 test = ["Aqua", "DiffEqBase", "Enzyme", "ExplicitImports", "InteractiveUtils", "NonlinearProblemLibrary", "Pkg", "PolyesterForwardDiff", "Random", "ReverseDiff", "StaticArrays", "Test", "TestItemRunner", "Tracker", "Zygote"]
+
+[sources]
+NonlinearSolveBase = {path = "../NonlinearSolveBase"}
diff --git a/src/NonlinearSolve.jl b/src/NonlinearSolve.jl
@@ -118,6 +118,6 @@ export NonlinearSolvePolyAlgorithm, FastShortcutNonlinearPolyalg, FastShortcutNL
 # Extension Algorithms
 export LeastSquaresOptimJL, FastLevenbergMarquardtJL, NLsolveJL, NLSolversJL,
        FixedPointAccelerationJL, SpeedMappingJL, SIAMFANLEquationsJL
-export PETScSNES, CMINPACK
+export PETScSNES, GridapPETScSNES, CMINPACK
 
 end
diff --git a/src/extension_algs.jl b/src/extension_algs.jl
@@ -488,3 +488,16 @@ function PETScSNES(; petsclib = missing, autodiff = nothing, mpi_comm = missing,
     end
     return PETScSNES(petsclib, mpi_comm, autodiff, kwargs)
 end
+
+# TODO: Docs
+@concrete struct GridapPETScSNES <: AbstractNonlinearSolveAlgorithm
+    autodiff
+    snes_options
+end
+
+function GridapPETScSNES(; autodiff = nothing, kwargs...)
+    if Base.get_extension(@__MODULE__, :NonlinearSolveGridapPETScExt) === nothing
+        error("`GridapPETScSNES` requires `GridapPETSc.jl` to be loaded")
+    end
+    return GridapPETScSNES(autodiff, kwargs)
+end