`reduce(vcat` returns corrupted result

[jkrumbiegel]

Something weird happens to the units in the reduce(vcat version, you can see already in the printout that the values differ. 1.0 hr vs (1.0 ) hr. I only noticed this later though, because uexpand then throws an error on these values.

julia> using DynamicQuantities

julia> arr1 = QuantityArray([us"hr"])
1-element QuantityArray(::Vector{Float64}, ::DynamicQuantities.Quantity{Float64, SymbolicDimensions{DynamicQuantities.FixedRational{Int32, 25200}}}):
 1.0 hr

julia> arr2 = QuantityArray([us"hr"])
1-element QuantityArray(::Vector{Float64}, ::DynamicQuantities.Quantity{Float64, SymbolicDimensions{DynamicQuantities.FixedRational{Int32, 25200}}}):
 1.0 hr

julia> arr3 = vcat(arr1, arr2)
2-element QuantityArray(::Vector{Float64}, ::DynamicQuantities.Quantity{Float64, SymbolicDimensions{DynamicQuantities.FixedRational{Int32, 25200}}}):
 1.0 hr
 1.0 hr

julia> DynamicQuantities.uexpand(arr3)
2-element QuantityArray(::Vector{Float64}, ::DynamicQuantities.Quantity{Float64, Dimensions{DynamicQuantities.FixedRational{Int32, 25200}}}):
 3600.0 s
 3600.0 s

julia> arr4 = reduce(vcat, [arr1, arr2])
2-element QuantityArray(::Vector{DynamicQuantities.Quantity{Float64, SymbolicDimensions{DynamicQuantities.FixedRational{Int32, 25200}}}}, ::DynamicQuantities.Quantity{DynamicQuantities.Quantity{Float64, SymbolicDimensions{DynamicQuantities.FixedRational{Int32, 25200}}}, SymbolicDimensions{DynamicQuantities.FixedRational{Int32, 25200}}}):
 (1.0 ) hr
 (1.0 ) hr

julia> DynamicQuantities.uexpand(arr4)
ERROR: MethodError: no method matching unsafe_fixed_rational(::DynamicQuantities.Quantity{Int32, SymbolicDimensions{DynamicQuantities.FixedRational{Int32, 25200}}}, ::Type{Int32}, ::Val{25200})

Closest candidates are:
  unsafe_fixed_rational(::Integer, ::Type{T}, ::Val{den}) where {T, den}
   @ DynamicQuantities ~/.julia/packages/DynamicQuantities/kwSjp/src/fixed_rational.jl:15

Stacktrace:
  [1] tryrationalize(#unused#::Type{DynamicQuantities.FixedRational{Int32, 25200}}, x::DynamicQuantities.Quantity{Float64, SymbolicDimensions{DynamicQuantities.FixedRational{Int32, 25200}}})
    @ DynamicQuantities ~/.julia/packages/DynamicQuantities/kwSjp/src/fixed_rational.jl:116
  [2] _pow(l::DynamicQuantities.Quantity{Float64, SymbolicDimensions{DynamicQuantities.FixedRational{Int32, 25200}}}, r::DynamicQuantities.Quantity{Float64, SymbolicDimensions{DynamicQuantities.FixedRational{Int32, 25200}}})
    @ DynamicQuantities ~/.julia/packages/DynamicQuantities/kwSjp/src/math.jl:119
  [3] ^(l::DynamicQuantities.Quantity{Float64, SymbolicDimensions{DynamicQuantities.FixedRational{Int32, 25200}}}, r::DynamicQuantities.Quantity{Float64, SymbolicDimensions{DynamicQuantities.FixedRational{Int32, 25200}}})
    @ DynamicQuantities ~/.julia/packages/DynamicQuantities/kwSjp/src/math.jl:127
  [4] _pow(l::DynamicQuantities.Quantity{DynamicQuantities.Quantity{Float64, SymbolicDimensions{DynamicQuantities.FixedRational{Int32, 25200}}}, Dimensions{DynamicQuantities.FixedRational{Int32, 25200}}}, r::DynamicQuantities.FixedRational{Int32, 25200})
    @ DynamicQuantities ~/.julia/packages/DynamicQuantities/kwSjp/src/math.jl:122
  [5] ^(l::DynamicQuantities.Quantity{DynamicQuantities.Quantity{Float64, SymbolicDimensions{DynamicQuantities.FixedRational{Int32, 25200}}}, Dimensions{DynamicQuantities.FixedRational{Int32, 25200}}}, r::DynamicQuantities.FixedRational{Int32, 25200})
    @ DynamicQuantities ~/.julia/packages/DynamicQuantities/kwSjp/src/math.jl:127
  [6] convert(#unused#::Type{DynamicQuantities.Quantity{DynamicQuantities.Quantity{Float64, SymbolicDimensions{DynamicQuantities.FixedRational{Int32, 25200}}}, Dimensions{DynamicQuantities.FixedRational{Int32, 25200}}}}, q::DynamicQuantities.Quantity{DynamicQuantities.Quantity{Float64, SymbolicDimensions{DynamicQuantities.FixedRational{Int32, 25200}}}, SymbolicDimensions{DynamicQuantities.FixedRational{Int32, 25200}}})
    @ DynamicQuantities ~/.julia/packages/DynamicQuantities/kwSjp/src/symbolic_dimensions.jl:94
  [7] uexpand
    @ ~/.julia/packages/DynamicQuantities/kwSjp/src/symbolic_dimensions.jl:113 [inlined]
  [8] materialize_first
    @ ~/.julia/packages/DynamicQuantities/kwSjp/src/arrays.jl:177 [inlined]
  [9] similar
    @ ~/.julia/packages/DynamicQuantities/kwSjp/src/arrays.jl:161 [inlined]
 [10] similar
    @ ~/.julia/packages/DynamicQuantities/kwSjp/src/arrays.jl:160 [inlined]
 [11] copy
    @ ./broadcast.jl:898 [inlined]
 [12] materialize
    @ ./broadcast.jl:873 [inlined]
 [13] uexpand(q::QuantityArray{DynamicQuantities.Quantity{Float64, SymbolicDimensions{DynamicQuantities.FixedRational{Int32, 25200}}}, 1, SymbolicDimensions{DynamicQuantities.FixedRational{Int32, 25200}}, DynamicQuantities.Quantity{DynamicQuantities.Quantity{Float64, SymbolicDimensions{DynamicQuantities.FixedRational{Int32, 25200}}}, SymbolicDimensions{DynamicQuantities.FixedRational{Int32, 25200}}}, Vector{DynamicQuantities.Quantity{Float64, SymbolicDimensions{DynamicQuantities.FixedRational{Int32, 25200}}}}})
    @ DynamicQuantities ~/.julia/packages/DynamicQuantities/kwSjp/src/symbolic_dimensions.jl:115
 [14] top-level scope
    @ REPL[63]:1

This was run on [06fc5a27] DynamicQuantities v0.10.0

[MilesCranmer]

Weird. I think we need an automatic way to go from

QuantityArray(::Vector{<:DynamicQuantities.Quantity})

back to a regular quantity array. Which should happen but for some reason it's not.