Describe the bug 🐞
It looks like AL_alg.jl does not update constraints violation when we use R2N or R2 as subsolver and these subsolvers do 0 iteration. Then if cviol = 0.0 at the first AL iteration, constraints violation are never updated so cviol is always equal to 0 even if the iterates induce constraints violation.
At the end, the solution can violate constraints but cviol = 0 is is displayed by the AL solver.
Expected behavior
If the iterates violate constraints, the solver should not display cviol = 0.
In addition, if cviol = 0, the condition
if cviol > max(ctol, factor_primal_linear_improvement * cviol_old)
mu *= factor_penalty_up
end
is never respected so iterates will make it difficult to meet the constraints later on, even if that isn't the case.
Minimal Reproducible Example 👇
In this exemple AL return cviol = 0 even if the real cviol is equal to 4.4.
h = NormL1(2.5)
meta = OptimizationProblems.meta
problem = "hs6"
nlp = OptimizationProblems.ADNLPProblems.eval(Meta.parse(problem))()
quadratic_model = QuadraticModel(nlp, nlp.meta.x0, name = nlp.meta.name)
nlp_quadra = RegularizedNLPModel(quadratic_model, h)
b = nlp_quadra.model.meta.lcon
solver = ALSolver(nlp_quadra; subsolver = R2Solver)
stats = GenericExecutionStats(nlp_quadra.model)
RegularizedOptimization.solve!(solver, nlp_quadra, stats, verbose = 1)
println("b: ", b)
println("cons: ", cons(nlp_quadra.model, stats.solution))
println("cviol: ", norm(cons(nlp_quadra.model, stats.solution) - b))
Error & Stacktrace ⚠️
[ Info: iter sub_it obj cviol μ normy sub_tol sub_status
[ Info: 0 0 2.4e+00 0.0e+00 1.0e+01 0.0e+00 1.0e-01
[ Info: 1 0 2.4e+00 0.0e+00 1.0e+01 0.0e+00 1.0e-01 first_order
[ Info: 2 0 2.4e+00 0.0e+00 1.0e+01 0.0e+00 2.5e-02 first_order
[ Info: 3 0 2.4e+00 0.0e+00 1.0e+01 0.0e+00 6.3e-03 first_order
[ Info: 4 0 2.4e+00 0.0e+00 1.0e+01 0.0e+00 1.6e-03 first_order
[ Info: 5 0 2.4e+00 0.0e+00 1.0e+01 0.0e+00 3.9e-04 first_order
[ Info: 6 0 2.4e+00 0.0e+00 1.0e+01 0.0e+00 9.8e-05 first_order
[ Info: 7 0 2.4e+00 0.0e+00 1.0e+01 0.0e+00 2.4e-05 first_order
[ Info: 8 0 2.4e+00 0.0e+00 1.0e+01 0.0e+00 6.1e-06 first_order
[ Info: 9 0 2.4e+00 0.0e+00 1.0e+01 0.0e+00 6.1e-06 first_order
b: [4.399]
cons: [0.0]
cviol: 4.399
Environment (please complete the following information):
- Output of
using Pkg; Pkg.status()
[54578032] ADNLPModels v0.8.13
[a4795742] NLPModels v0.21.12
[5049e819] OptimizationProblems v0.9.3
[a725b495] ProximalOperators v0.16.1
[f468eda6] QuadraticModels v0.9.16
[20620ad1] RegularizedOptimization v0.3.2
[ea076b23] RegularizedProblems v0.1.5
[ff4d7338] SolverCore v0.3.10
[37e2e46d] LinearAlgebra v1.12.0
- Output of
using Pkg; Pkg.status(; mode = PKGMODE_MANIFEST)
[54578032] ADNLPModels v0.8.13
[47edcb42] ADTypes v1.22.0
[621f4979] AbstractFFTs v1.5.0
[79e6a3ab] Adapt v4.6.1
[66dad0bd] AliasTables v1.1.3
[7d9fca2a] Arpack v0.5.4
[d360d2e6] ChainRulesCore v1.26.1
[0b6fb165] ChunkCodecCore v1.0.1
[4c0bbee4] ChunkCodecLibZlib v1.0.0
[55437552] ChunkCodecLibZstd v1.0.0
[523fee87] CodecBzip2 v0.8.5
[944b1d66] CodecZlib v0.7.8
⌅ [3da002f7] ColorTypes v0.11.5
⌅ [5ae59095] Colors v0.12.11
[38540f10] CommonSolve v0.2.7
[bbf7d656] CommonSubexpressions v0.3.1
[34da2185] Compat v4.18.1
[187b0558] ConstructionBase v1.6.0
[a8cc5b0e] Crayons v4.1.1
[9a962f9c] DataAPI v1.16.0
[a93c6f00] DataFrames v1.8.2
[864edb3b] DataStructures v0.19.5
[e2d170a0] DataValueInterfaces v1.0.0
[163ba53b] DiffResults v1.1.0
[b552c78f] DiffRules v1.16.0
[31c24e10] Distributions v0.25.126
[ffbed154] DocStringExtensions v0.9.5
[e2ba6199] ExprTools v0.1.10
[9aa1b823] FastClosures v0.3.2
[5789e2e9] FileIO v1.19.0
[1a297f60] FillArrays v1.16.0
⌅ [53c48c17] FixedPointNumbers v0.8.6
[f6369f11] ForwardDiff v1.4.0
[069b7b12] FunctionWrappers v1.1.3
[a2bd30eb] Graphics v1.1.3
[076d061b] HashArrayMappedTries v0.2.0
[34004b35] HypergeometricFunctions v0.3.28
⌅ [a09fc81d] ImageCore v0.8.22
[842dd82b] InlineStrings v1.4.5
[41ab1584] InvertedIndices v1.3.1
[92d709cd] IrrationalConstants v0.2.6
[42fd0dbc] IterativeSolvers v0.9.4
[82899510] IteratorInterfaceExtensions v1.0.0
[033835bb] JLD2 v0.6.4
[692b3bcd] JLLWrappers v1.8.0
[682c06a0] JSON v1.6.1
[10dff2fc] JSOSolvers v0.14.8
[4076af6c] JuMP v1.30.1
[ba0b0d4f] Krylov v0.10.6
[b964fa9f] LaTeXStrings v1.4.0
[5c8ed15e] LinearOperators v2.14.1
⌅ [2ab3a3ac] LogExpFunctions v0.3.29
[1914dd2f] MacroTools v0.5.16
[30dfa513] ManualNLPModels v0.2.0
[dbb5928d] MappedArrays v0.4.3
[b8f27783] MathOptInterface v1.51.1
[e1d29d7a] Missings v1.2.0
[e94cdb99] MosaicViews v0.3.4
[d8a4904e] MutableArithmetics v1.8.0
[a4795742] NLPModels v0.21.12
⌅ [e01155f1] NLPModelsModifiers v0.7.4
[77ba4419] NaNMath v1.1.3
⌅ [81d43f40] Noise v0.2.2
[ab2f91bb] OSQP v0.8.1
[6fe1bfb0] OffsetArrays v1.17.0
[5049e819] OptimizationProblems v0.9.3
⌅ [bac558e1] OrderedCollections v1.8.2
[90014a1f] PDMats v0.11.37
[5432bcbf] PaddedViews v0.5.12
[69de0a69] Parsers v2.8.5
[01435c0c] Percival v0.7.6
[e409e4f3] PoissonRandom v0.4.9
[2dfb63ee] PooledArrays v1.4.3
[aea7be01] PrecompileTools v1.3.4
[21216c6a] Preferences v1.5.2
[08abe8d2] PrettyTables v3.3.2
⌅ [dc4f5ac2] ProximalCore v0.1.2
[a725b495] ProximalOperators v0.16.1
[43287f4e] PtrArrays v1.4.0
[422b30a1] QRMumps v0.3.2
[1fd47b50] QuadGK v2.11.3
[f468eda6] QuadraticModels v0.9.16
[3cdcf5f2] RecipesBase v1.3.4
[189a3867] Reexport v1.2.2
[20620ad1] RegularizedOptimization v0.3.2
[ea076b23] RegularizedProblems v0.1.5
[ae029012] Requires v1.3.1
[37e2e3b7] ReverseDiff v1.16.2
[79098fc4] Rmath v0.9.0
⌅ [f2b01f46] Roots v1.4.1
[7e506255] ScopedValues v1.6.2
[91c51154] SentinelArrays v1.4.10
⌅ [efcf1570] Setfield v0.8.3
[d4fd37fa] ShiftedProximalOperators v0.2.4
[ff4d7338] SolverCore v0.3.10
[d076d87d] SolverParameters v0.1.2
[b5612192] SolverTools v0.10.1
[a2af1166] SortingAlgorithms v1.2.2
[9f842d2f] SparseConnectivityTracer v1.2.1
[fa32481b] SparseMatricesCOO v0.2.6
[0a514795] SparseMatrixColorings v0.4.27
[276daf66] SpecialFunctions v2.8.0
[cae243ae] StackViews v0.1.2
[90137ffa] StaticArrays v1.9.18
[1e83bf80] StaticArraysCore v1.4.4
[10745b16] Statistics v1.11.1
[82ae8749] StatsAPI v1.8.0
[2913bbd2] StatsBase v0.34.11
[4c63d2b9] StatsFuns v2.1.0
[892a3eda] StringManipulation v0.4.4
[ec057cc2] StructUtils v2.8.2
[9449cd9e] TSVD v0.4.4
[3783bdb8] TableTraits v1.0.1
[bd369af6] Tables v1.12.1
[a759f4b9] TimerOutputs v0.5.29
[3bb67fe8] TranscodingStreams v0.11.3
⌅ [68821587] Arpack_jll v3.5.2+0
[6e34b625] Bzip2_jll v1.0.9+0
[d00139f3] METIS_jll v5.1.3+0
[9c4f68bf] OSQP_jll v0.600.200+0
[656ef2d0] OpenBLAS32_jll v0.3.33+1
[efe28fd5] OpenSpecFun_jll v0.5.6+0
[f50d1b31] Rmath_jll v0.5.1+0
[a8d0f55d] SCOTCH_jll v7.0.11+0
[ffd25f8a] XZ_jll v5.8.3+0
[3161d3a3] Zstd_jll v1.5.7+1
[e37b5aa0] qr_mumps_jll v3.1.1+0
[0dad84c5] ArgTools v1.1.2
[56f22d72] Artifacts v1.11.0
[2a0f44e3] Base64 v1.11.0
[ade2ca70] Dates v1.11.0
[f43a241f] Downloads v1.7.0
[7b1f6079] FileWatching v1.11.0
[9fa8497b] Future v1.11.0
[b77e0a4c] InteractiveUtils v1.11.0
[ac6e5ff7] JuliaSyntaxHighlighting v1.12.0
[b27032c2] LibCURL v0.6.4
[76f85450] LibGit2 v1.11.0
[8f399da3] Libdl v1.11.0
[37e2e46d] LinearAlgebra v1.12.0
[56ddb016] Logging v1.11.0
[d6f4376e] Markdown v1.11.0
[a63ad114] Mmap v1.11.0
[ca575930] NetworkOptions v1.3.0
[44cfe95a] Pkg v1.12.1
[de0858da] Printf v1.11.0
[3fa0cd96] REPL v1.11.0
[9a3f8284] Random v1.11.0
[ea8e919c] SHA v0.7.0
[9e88b42a] Serialization v1.11.0
[6462fe0b] Sockets v1.11.0
[2f01184e] SparseArrays v1.12.0
[f489334b] StyledStrings v1.11.0
[4607b0f0] SuiteSparse
[fa267f1f] TOML v1.0.3
[a4e569a6] Tar v1.10.0
[8dfed614] Test v1.11.0
[cf7118a7] UUIDs v1.11.0
[4ec0a83e] Unicode v1.11.0
[e66e0078] CompilerSupportLibraries_jll v1.3.0+1
[deac9b47] LibCURL_jll v8.15.0+0
[e37daf67] LibGit2_jll v1.9.0+0
[29816b5a] LibSSH2_jll v1.11.3+1
[14a3606d] MozillaCACerts_jll v2025.11.4
[4536629a] OpenBLAS_jll v0.3.29+0
[05823500] OpenLibm_jll v0.8.7+0
[458c3c95] OpenSSL_jll v3.5.4+0
[bea87d4a] SuiteSparse_jll v7.8.3+2
[83775a58] Zlib_jll v1.3.1+2
[8e850b90] libblastrampoline_jll v5.15.0+0
[8e850ede] nghttp2_jll v1.64.0+1
[3f19e933] p7zip_jll v17.7.0+0
Julia Version 1.12.6
Commit 15346901f00 (2026-04-09 19:20 UTC)
Build Info:
Official https://julialang.org release
Platform Info:
OS: macOS (arm64-apple-darwin24.0.0)
CPU: 8 × Apple M1
WORD_SIZE: 64
LLVM: libLLVM-18.1.7 (ORCJIT, apple-m1)
GC: Built with stock GC
Threads: 1 default, 1 interactive, 1 GC (on 4 virtual cores)
Describe the bug 🐞
It looks like
AL_alg.jldoes not update constraints violation when we useR2NorR2as subsolver and these subsolvers do 0 iteration. Then ifcviol = 0.0at the firstALiteration, constraints violation are never updated socviolis always equal to 0 even if the iterates induce constraints violation.At the end, the solution can violate constraints but
cviol = 0is is displayed by theALsolver.Expected behavior
If the iterates violate constraints, the solver should not display
cviol = 0.In addition, if
cviol = 0, the conditionis never respected so iterates will make it difficult to meet the constraints later on, even if that isn't the case.
Minimal Reproducible Example 👇
In this exemple
ALreturncviol = 0even if the realcviolis equal to 4.4.Error & Stacktrace⚠️
Environment (please complete the following information):
using Pkg; Pkg.status()using Pkg; Pkg.status(; mode = PKGMODE_MANIFEST)versioninfo()