Base.quadgk fails with Unitful

[ggggggggg]

My guess is that this issue actually arises from Base, but it seems worth having someone with more knowledge look at it first. The docs for quadgk claim that it should work with any type that implements, +, -, multiplication by real values, and norm; all of which seem to work with Quantity.

julia> using Unitful

julia> quadgk(x->x*1u"mm",0,1)
ERROR: Unitful.DimensionError()
 in convfact(...) at /Users/oneilg/.julia/v0.5/Unitful/src/Conversion.jl:79
 in convert at /Users/oneilg/.julia/v0.5/Unitful/src/Conversion.jl:183 [inlined]
 in Base.QuadGK.Segment(::Float64, ::Float64, ::Unitful.Quantity{Float64,Unitful.Dimensions{(Unitful.Dimension{:Length}(1//1),)},Unitful.Units{(Unitful.Unit{:Meter}(-3,1//1),),Unitful.Dimensions{(Unitful.Dimension{:Length}(1//1),)}}}, ::Unitful.Quantity{Float64,Unitful.Dimensions{(Unitful.Dimension{:Length}(1//1),)},Unitful.Units{(Unitful.Unit{:Meter}(-3,1//1),),Unitful.Dimensions{(Unitful.Dimension{:Length}(1//1),)}}}) at ./quadgk.jl:40
 in evalrule(::##1#2, ::Float64, ::Float64, ::Array{Float64,1}, ::Array{Float64,1}, ::Array{Float64,1}, ::Base.LinAlg.#vecnorm) at ./quadgk.jl:79
 in do_quadgk(::##1#2, ::Array{Float64,1}, ::Int64, ::Type{Float64}, ::Float64, ::Float64, ::Int64, ::Base.LinAlg.#vecnorm) at ./quadgk.jl:120
 in #quadgk#15(::Array{Any,1}, ::Function, ::Function, ::Int64, ::Int64) at ./quadgk.jl:230
 in quadgk(::Function, ::Int64, ::Int64) at ./quadgk.jl:225

[ajkeller34]

I have a fix for this but it won't be ready until julia 0.6. When it is ready, then you should be able to integrate Quantity-valued functions and also integrate over a unitful domain.

[ajkeller34]

Actually, the fix is ready now on Julia 0.5. Just clone UnitfulIntegration.jl and it should work with the most recent release of Unitful and the QuadGK.jl package. I will tag and release UnitfulIntegration sometime this month. The functionality is located in a separate package to avoid adding dependencies to Unitful.

Be sure to do QuadGK.quadgk(...) instead of just quadgk on Julia 0.5 otherwise you'll call the quadgk implementation in Julia Base which is not compatible. In Julia 0.6 quadgk is no longer in Base so this won't be a problem.