x-ref: https://discourse.julialang.org/t/jump-broadcasting-in-constraint-involving-expressions-throws-error/82044
julia> using JuMP
julia> model = JuMP.Model()
A JuMP Model
Feasibility problem with:
Variables: 0
Model mode: AUTOMATIC
CachingOptimizer state: NO_OPTIMIZER
Solver name: No optimizer attached.
julia> @expression(model, x, zeros(AffExpr, 1, 4))
1×4 Matrix{AffExpr}:
0 0 0 0
julia> @expression(model, y, zeros(AffExpr, 2, 4))
2×4 Matrix{AffExpr}:
0 0 0 0
0 0 0 0
julia> @constraint(model, y .>= x) # A: OK
2×4 Matrix{ConstraintRef{Model, MathOptInterface.ConstraintIndex{MathOptInterface.ScalarAffineFunction{Float64}, MathOptInterface.GreaterThan{Float64}}, ScalarShape}}:
0 ≥ 0.0 0 ≥ 0.0 0 ≥ 0.0 0 ≥ 0.0
0 ≥ 0.0 0 ≥ 0.0 0 ≥ 0.0 0 ≥ 0.0
julia> @constraint(model, x .<= y)
ERROR: DimensionMismatch("destination axes (Base.OneTo(1), Base.OneTo(4)) are not compatible with source axes (Base.OneTo(2), Base.OneTo(4))")
Stacktrace:
[1] throwdm(axdest::Tuple{Base.OneTo{Int64}, Base.OneTo{Int64}}, axsrc::Tuple{Base.OneTo{Int64}, Base.OneTo{Int64}})
@ Base.Broadcast ./broadcast.jl:1060
[2] copyto!
@ ./broadcast.jl:972 [inlined]
[3] copyto!
@ ./broadcast.jl:936 [inlined]
[4] broadcast!(op::typeof(MutableArithmetics.sub_mul), A::Matrix{AffExpr}, args::Matrix{AffExpr})
@ MutableArithmetics ~/.julia/packages/MutableArithmetics/VLWSd/src/broadcast.jl:117
[5] broadcast_fallback!
@ ~/.julia/packages/MutableArithmetics/VLWSd/src/broadcast.jl:173 [inlined]
[6] broadcast!!(::typeof(MutableArithmetics.sub_mul), ::Matrix{AffExpr}, ::Matrix{AffExpr})
@ MutableArithmetics ~/.julia/packages/MutableArithmetics/VLWSd/src/broadcast.jl:145
[7] macro expansion
@ ~/.julia/packages/MutableArithmetics/VLWSd/src/rewrite.jl:294 [inlined]
[8] macro expansion
@ ~/.julia/dev/JuMP/src/macros.jl:823 [inlined]
[9] top-level scope
@ REPL[6]:1
