LinearAlgebra.norm {sum?} fails after 9.72.0 with vectors

[RobbesU]

Describe the example

My 3D-bodies system worked fine under 9.72.
Upgraded last week (9.79 at the time, currently 9.80) and got two distinct failure messages.

• during the @named get error "Failed to show value: cannot latexify objects of type Pair{Symbol, Bool}" (despite output being suppressed with ";")
• during the structural_simplify now getting an "ExtraVariablesSystemException: The system is unbalanced."

I eventually traced it to the use of LinearAlgebra.norm() in Equations (to get length of vectors), and splitting that out into its components shows it also fails using sum().

Loading specific versions it appears the error started in 9.73

FWIW: I'm working in Pluto notebook.

Minimal Reproducible Example 👇

using ModelingToolkit          # reexports e.g. Symbolics
using LinearAlgebra: LinearAlgebra as LA
using ModelingToolkit: t_nounits as t, D_nounits as D

@component function MWE(;name, l0=1.0)
	
	pars = @parameters begin
        l0=l0, [description = "Spring length at rest in [m]"]
	end
	
	vars = @variables begin
                 l(t),        [description = "Spring length in [m]"]
		Δl(t),       [description = "Spring strech [m/]"]

		l3_sq(t)[1:3]   # purely for MWE
		s2_mwe(t)[1:3]  # purely for MWE, pos vector normally comes from Flange.s
	end

	
	eqs = [
		collect( s2_mwe .~ [sin(t), 0.0, 0.0])...
		
		l ~ LA.norm(s2_mwe )  # "Failed to show value: cannot latexify objects of type Pair{Symbol, Bool}"
		#collect(l3_sq .~ (s2_mwe).^2)...   # This works !
		
		#l  ~ sum(l3_sq) # "Failed to show value: cannot latexify objects of type Pair{Symbol, Bool}"
		l ~ l3_sq[1] + l3_sq[2] + l3_sq[3]  # This works
		#l ~ l3_sq[1]+l3_sq[2]+l3_sq[3]  # This works
		#l ~ l3_sq[1] +l3_sq[2] +l3_sq[3]  # Fails: "DimensionMismatch: number of columns of each array must match (got (3, 3, 3, 1))"
		
		Δl ~ (l - l0)
		
	]
	ODESystem(eqs, t, vars, pars; name)
end

@named mwe_sys0 = MWE(l0=1.0)

mwe_sys = structural_simplify(mwe_sys0)  

Error & Stacktrace ⚠️

Error message from Latexify

Failed to show value: 

cannot latexify objects of type Pair{Symbol, Bool}
Stack trace

Here is what happened, the most recent locations are first:

    #_latexraw#45(args::Pair{…}; kwargs::@Kwargs{…}) [...show types...](http://localhost:1234/edit?id=10b2c9e0-3a07-11f0-0d80-cf0133a16f49#)
    from 
    Latexify → latexraw.jl:110
    #process_latexify#166(args::Pair{…}; kwargs::@Kwargs{…}) [...show types...](http://localhost:1234/edit?id=10b2c9e0-3a07-11f0-0d80-cf0133a16f49#)
    from 
    Latexify → latexify_function.jl:49
    process_latexify
    from 
    latexify_function.jl:40
    latexraw
    from 
    latexraw.jl:58
    #_latexarray#75(arr::Vector{…}; adjustment::Symbol, transpose::Bool, double_linebreak::Bool, starred::Bool, arraystyle::Symbol, kwargs::@Kwargs{…}) [...show types...](http://localhost:1234/edit?id=10b2c9e0-3a07-11f0-0d80-cf0133a16f49#)
    from 
    Latexify → latexarray.jl:57
    _latexarray
    from 
    latexarray.jl:17
    #_latexarray#81
    from 
    latexarray.jl:79
    _latexarray
    from 
    latexarray.jl:75
    #_latexraw#46
    from 
    latexraw.jl:113
    #process_latexify#166(args::Tuple{…}; kwargs::@Kwargs{…}) [...show types...](http://localhost:1234/edit?id=10b2c9e0-3a07-11f0-0d80-cf0133a16f49#)
    from 
    Latexify → latexify_function.jl:49
    process_latexify
    from 
    latexify_function.jl:40
    latexraw
    from 
    latexraw.jl:58
    anonymous function(i::Tuple{…}) [...show types...](http://localhost:1234/edit?id=10b2c9e0-3a07-11f0-0d80-cf0133a16f49#)
    from 
    Latexify → latexoperation.jl:27
    iterate
    from 
    generator.jl:48
    collect_to!(dest::Vector{…}, itr::Base.Generator{…}, offs::Int64, st::Int64) [...show types...](http://localhost:1234/edit?id=10b2c9e0-3a07-11f0-0d80-cf0133a16f49#)
    from 
    [julia → array.jl:849](https://github.com/JuliaLang/julia/tree/760b2e5b7396f9cc0da5efce0cadd5d1974c4069/base/array.jl#L844)
     

collect_to!(dest::Vector{…}, itr::Base.Generator{…}, offs::Int64, st::Int64) [...show types...](http://localhost:1234/edit?id=10b2c9e0-3a07-11f0-0d80-cf0133a16f49#)
from 
[julia → array.jl:857](https://github.com/JuliaLang/julia/tree/760b2e5b7396f9cc0da5efce0cadd5d1974c4069/base/array.jl#L844)
 
collect_to_with_first!(dest::Vector{…}, v1::LaTeXStrings.LaTeXString, itr::Base.Generator{…}, st::Int64) [...show types...](http://localhost:1234/edit?id=10b2c9e0-3a07-11f0-0d80-cf0133a16f49#)
from 
[julia → array.jl:827](https://github.com/JuliaLang/julia/tree/760b2e5b7396f9cc0da5efce0cadd5d1974c4069/base/array.jl#L824)
 
_collect(c::Vector{…}, itr::Base.Generator{…}, ::Base.EltypeUnknown, isz::Base.HasShape{…}) [...show types...](http://localhost:1234/edit?id=10b2c9e0-3a07-11f0-0d80-cf0133a16f49#)
from 
[julia → array.jl:821](https://github.com/JuliaLang/julia/tree/760b2e5b7396f9cc0da5efce0cadd5d1974c4069/base/array.jl#L808)
 
collect_similar
from 
array.jl:720
map
from 
abstractarray.jl:3371
#latexoperation#62(ex::Expr, prevOp::Vector{…}; kwargs::@Kwargs{…}) [...show types...](http://localhost:1234/edit?id=10b2c9e0-3a07-11f0-0d80-cf0133a16f49#)
from 
Latexify → latexoperation.jl:27
latexoperation
from 
latexoperation.jl:9
recurseexp!(ex::Expr) [...show types...](http://localhost:1234/edit?id=10b2c9e0-3a07-11f0-0d80-cf0133a16f49#)
from 
Latexify → latexraw.jl:97
recurseexp!(ex::Expr) [...show types...](http://localhost:1234/edit?id=10b2c9e0-3a07-11f0-0d80-cf0133a16f49#)
from 
Latexify → latexraw.jl:92
#_latexraw#41(inputex::Expr; convert_unicode::Bool, kwargs::@Kwargs{…}) [...show types...](http://localhost:1234/edit?id=10b2c9e0-3a07-11f0-0d80-cf0133a16f49#)
from 
Latexify → latexraw.jl:101
#process_latexify#166(args::Symbolics.Num; kwargs::@Kwargs{…}) [...show types...](http://localhost:1234/edit?id=10b2c9e0-3a07-11f0-0d80-cf0133a16f49#)
from 
Latexify → latexify_function.jl:49
process_latexify
from 
latexify_function.jl:40
latexraw
from 
latexraw.jl:58
anonymous function
from 
broadcast.jl:1311
_broadcast_getindex_evalf
from 
broadcast.jl:678
_broadcast_getindex
from 
broadcast.jl:651
getindex
from 
broadcast.jl:610
copyto_nonleaf!(dest::Matrix{…}, bc::Base.Broadcast.Broadcasted{…}, iter::CartesianIndices{…}, state::CartesianIndex{…}, count::Int64) [...show types...](http://localhost:1234/edit?id=10b2c9e0-3a07-11f0-0d80-cf0133a16f49#)
from 
[julia → broadcast.jl:1082](https://github.com/JuliaLang/julia/tree/760b2e5b7396f9cc0da5efce0cadd5d1974c4069/base/broadcast.jl#L1076)
 
restart_copyto_nonleaf!(newdest::Matrix{…}, dest::Matrix{…}, bc::Base.Broadcast.Broadcasted{…}, val::String, I::CartesianIndex{…}, iter::CartesianIndices{…}, state::CartesianIndex{…}, count::Int64) [...show types...](http://localhost:1234/edit?id=10b2c9e0-3a07-11f0-0d80-cf0133a16f49#)
from 
[julia → broadcast.jl:1073](https://github.com/JuliaLang/julia/tree/760b2e5b7396f9cc0da5efce0cadd5d1974c4069/base/broadcast.jl#L1067)
 
copyto_nonleaf!(dest::Matrix{…}, bc::Base.Broadcast.Broadcasted{…}, iter::CartesianIndices{…}, state::CartesianIndex{…}, count::Int64) [...show types...](http://localhost:1234/edit?id=10b2c9e0-3a07-11f0-0d80-cf0133a16f49#)
from 
[julia → broadcast.jl:1089](https://github.com/JuliaLang/julia/tree/760b2e5b7396f9cc0da5efce0cadd5d1974c4069/base/broadcast.jl#L1076)
 
copy
from 
broadcast.jl:919
materialize
from 
broadcast.jl:872
#_latexalign#85(arr::Matrix{…}; separator::String, double_linebreak::Bool, starred::Bool, rows::Symbol, aligned::Bool, kwargs::@Kwargs{…}) [...show types...](http://localhost:1234/edit?id=10b2c9e0-3a07-11f0-0d80-cf0133a16f49#)
from 
Latexify → latexalign.jl:46
#process_latexify#166(args::Matrix{…}; kwargs::@Kwargs{…}) [...show types...](http://localhost:1234/edit?id=10b2c9e0-3a07-11f0-0d80-cf0133a16f49#)
from 
Latexify → latexify_function.jl:49
process_latexify
from 
latexify_function.jl:40
latexalign
from 
latexalign.jl:42
#_latexalign#91
from 
latexalign.jl:87
#process_latexify#166(args::Vector{…}; kwargs::@Kwargs{}) [...show types...](http://localhost:1234/edit?id=10b2c9e0-3a07-11f0-0d80-cf0133a16f49#)
from 
Latexify → latexify_function.jl:49
process_latexify
from 
latexify_function.jl:40
#latexify#165(args::Vector{…}; kwargs::@Kwargs{}) [...show types...](http://localhost:1234/edit?id=10b2c9e0-3a07-11f0-0d80-cf0133a16f49#)
from 
Latexify → latexify_function.jl:27
latexify
from 
latexify_function.jl:25
macro expansion
from 
abstractsystem.jl:2581
#apply_recipe#392
from 
recipes.jl:174
apply_recipe
from 
recipes.jl:168
process_latexify(args::ModelingToolkit.ODESystem; kwargs::@Kwargs{})
from 
Latexify → latexify_function.jl:42
process_latexify
from 
latexify_function.jl:40
latexify(args::ModelingToolkit.ODESystem; kwargs::@Kwargs{})
from 
Latexify → latexify_function.jl:27
latexify
from 
latexify_function.jl:25
show(io::IOBuffer, ::MIME{…}, x::ModelingToolkit.ODESystem) [...show types...](http://localhost:1234/edit?id=10b2c9e0-3a07-11f0-0d80-cf0133a16f49#)
from 
ModelingToolkit → abstractsystem.jl:2585
__binrepr(m::MIME{…}, x::ModelingToolkit.ODESystem, context::Nothing) [...show types...](http://localhost:1234/edit?id=10b2c9e0-3a07-11f0-0d80-cf0133a16f49#)
from 
[julia → multimedia.jl:171](https://github.com/JuliaLang/julia/tree/760b2e5b7396f9cc0da5efce0cadd5d1974c4069/base/multimedia.jl#L168)
 
#repr#1(m::MIME{…}, x::ModelingToolkit.ODESystem; context::Nothing) [...show types...](http://localhost:1234/edit?id=10b2c9e0-3a07-11f0-0d80-cf0133a16f49#)
from 
[julia → multimedia.jl:159](https://github.com/JuliaLang/julia/tree/760b2e5b7396f9cc0da5efce0cadd5d1974c4069/base/multimedia.jl#L159)

Not Working Environment (please complete the following information):

• Output of using Pkg; Pkg.status()

  Activating project at `C:\Users\robur\OneDrive\Documents\Projects\pluto_notebooks\Notebooks_MTK\Env_MTK`
Status `C:\Users\robur\OneDrive\Documents\Projects\pluto_notebooks\Notebooks_MTK\Env_MTK\Project.toml`
  [5ae59095] Colors v0.13.1
  [a93c6f00] DataFrames v1.7.0
  [82cc6244] DataInterpolations v8.0.1
  [864edb3b] DataStructures v0.18.22
  [0c46a032] DifferentialEquations v7.16.1
⌅ [f6369f11] ForwardDiff v0.10.38
  [f7f18e0c] GLFW v3.4.4
  [e9467ef8] GLMakie v0.11.8
  [5c1252a2] GeometryBasics v0.5.9
  [b964fa9f] LaTeXStrings v1.4.0
  [961ee093] ModelingToolkit v9.80.1
  [16a59e39] ModelingToolkitStandardLibrary v2.21.1
  [1dea7af3] OrdinaryDiffEq v6.97.0
  [127b3ac7] OrdinaryDiffEqNonlinearSolve v1.9.0
  [91a5bcdd] Plots v1.40.13
  [7f904dfe] PlutoUI v0.7.62
  [94ee1d12] Quaternions v0.7.6
  [6038ab10] Rotations v1.7.1
  [0bca4576] SciMLBase v2.95.0
  [5c889d49] SkewLinearAlgebra v1.0.0
  [90137ffa] StaticArrays v1.9.13
  [10745b16] Statistics v1.11.1
  [37e2e46d] LinearAlgebra v1.11.0
  [de0858da] Printf v1.11.0
Info Packages marked with ⌅ have new versions available but compatibility constraints restrict them from upgrading. To see why use `status --outdated`

• Output of using Pkg; Pkg.status(; mode = PKGMODE_MANIFEST)

❔

Status `C:\Users\robur\OneDrive\Documents\Projects\pluto_notebooks\Notebooks_MTK\Env_MTK\Manifest.toml`
⌅ [3da002f7] ColorTypes v0.11.5 (<v0.12.1): ColorVectorSpace, PlutoUI
⌃ [c3611d14] ColorVectorSpace v0.10.0 (<v0.11.0)
⌅ [a0c0ee7d] DifferentiationInterface v0.6.54 (<v0.7.0): BoundaryValueDiffEqAscher, BoundaryValueDiffEqFIRK, BoundaryValueDiffEqMIRK, BoundaryValueDiffEqMIRKN, BoundaryValueDiffEqShooting, ModelingToolkit, NLSolversBase, OrdinaryDiffEqDifferentiation, OrdinaryDiffEqRosenbrock
⌅ [8fc22ac5] FilePaths v0.8.3 (<v0.9.0): Makie
⌅ [f6369f11] ForwardDiff v0.10.38 (<v1.0.1): DataInterpolations, ModelingToolkit, OrdinaryDiffEq, OrdinaryDiffEqDifferentiation, OrdinaryDiffEqNonlinearSolve, OrdinaryDiffEqRosenbrock
⌅ [a98d9a8b] Interpolations v0.15.1 (<v0.16.1): KernelDensity, Makie
⌅ [70703baa] JuliaSyntax v0.4.10 (<v1.0.2): JuliaFormatter
⌅ [aea7be01] PrecompileTools v1.2.1 (<v1.3.2): julia
⌅ [c0aeaf25] SciMLOperators v0.4.0 (<v1.3.0): NonlinearSolveBase, NonlinearSolveQuasiNewton, SciMLJacobianOperators, SparseDiffTools
⌃ [83423d85] Cairo_jll v1.18.4+0 (<v1.18.5+0)
⌅ [b22a6f82] FFMPEG_jll v4.4.4+1 (<v7.1.0+0): FFMPEG, Makie
⌃ [7746bdde] Glib_jll v2.82.4+0 (<v2.84.0+0)
⌅ [e9f186c6] Libffi_jll v3.2.2+2 (<v3.4.7+0): Glib_jll, HarfBuzz_jll, Wayland_jll
⌅ [30392449] Pixman_jll v0.44.2+0 (<v0.46.0+0): Cairo_jll
⌅ [fb77eaff] Sundials_jll v5.2.3+0 (<v6.6.0+0): Sundials
⌃ [a2964d1f] Wayland_jll v1.21.0+2 (<v1.23.1+0)
⌅ [02c8fc9c] XML2_jll v2.13.6+1 (<v2.14.1+0): Gettext_jll, Wayland_jll
⌅ [1270edf5] x264_jll v2021.5.5+0 (<v10164.0.1+0): FFMPEG_jll
⌅ [dfaa095f] x265_jll v3.5.0+0 (<v4.1.0+0): FFMPEG_jll

• Output of versioninfo()

❔

Julia Version 1.11.5
Commit 760b2e5b73 (2025-04-14 06:53 UTC)
Build Info:
  Official https://julialang.org/ release
Platform Info:
  OS: Windows (x86_64-w64-mingw32)
  CPU: 8 × Intel(R) Core(TM) i7-8565U CPU @ 1.80GHz
  WORD_SIZE: 64
  LLVM: libLLVM-16.0.6 (ORCJIT, skylake)
Threads: 4 default, 0 interactive, 2 GC (on 8 virtual cores)
Environment:
  JULIA_REVISE_WORKER_ONLY = 1

Additional context

Add any other context about the problem here.

[RobbesU]

Not sure at all if this is relevant, but a while ago I had a similar symbolic sum() issue... could it be related to JuliaSymbolics/Symbolics.jl#1433

[RobbesU]

For reference: This is the Pkg.status of the full working version

md"""
##### 15/4/25, V22   \
Status `C:\Users\robur\OneDrive\Documents\Projects\pluto_notebooks\Notebooks_MTK\Env_MTK\Project.toml`
  [5ae59095] Colors v0.13.0
  [a93c6f00] DataFrames v1.7.0
  [82cc6244] DataInterpolations v8.0.0
  [864edb3b] DataStructures v0.18.22
  [0c46a032] DifferentialEquations v7.16.1
⌅ [f6369f11] ForwardDiff v0.10.38
  [f7f18e0c] GLFW v3.4.3
  [e9467ef8] GLMakie v0.11.5
  [5c1252a2] GeometryBasics v0.5.7
  [b964fa9f] LaTeXStrings v1.4.0
  [961ee093] ModelingToolkit v9.72.0
  [16a59e39] ModelingToolkitStandardLibrary v2.19.1
  [1dea7af3] OrdinaryDiffEq v6.93.0
  [127b3ac7] OrdinaryDiffEqNonlinearSolve v1.6.0
  [91a5bcdd] Plots v1.40.12
  [7f904dfe] PlutoUI v0.7.62
  [94ee1d12] Quaternions v0.7.6
  [6038ab10] Rotations v1.7.1
  [5c889d49] SkewLinearAlgebra v1.0.0
  [90137ffa] StaticArrays v1.9.13
  [10745b16] Statistics v1.11.1
  [37e2e46d] LinearAlgebra v1.11.0
  [de0858da] Printf v1.11.0
"""

[RobbesU]

On further investigation, running the exact same code in VSCode passes.
So probably this one is a new issue with Pluto rather then MTK.
Pluto version doesn't show in the Pkg.status as i'm using dedicated project directories and Pluto lives in the native directory.

Pluto has only had minor updates in the past few weeks but version <0.020.5 no longer available so can't rewind to verify :-(

[ChrisRackauckas]

It's that the sum(A) doesn't seem to have a latex representation, and Pluto always prints out the latex. So the computation is fine but the print out bugs.

[RobbesU]

Thank you @ChrisRackauckas, I realised that but initially throught it was MTK that initiated the bug. I'll transfer the issue to Pluto/Latexify. Thanks again for a brilliant package!

[RobbesU]

Or is this a Symbolics.jl issue ?

[ChrisRackauckas]

This is for symbolics.