Plots.jl compatibility with SIUnits.jl

[ChrisRackauckas]

Currently Plots.jl is not compatible with SIUnits.jl:

julia> sol[:]
17-element Array{SIUnits.SIQuantity{Float64,1,1,-2,0,0,0,0,0,0},1}:
     1.5 kg m s⁻²
 1.54688 kg m s⁻²
 1.59521 kg m s⁻²
 1.64507 kg m s⁻²
 1.69647 kg m s⁻²
 1.74949 kg m s⁻²
 1.80416 kg m s⁻²
 1.86054 kg m s⁻²
 1.91868 kg m s⁻²
 1.97864 kg m s⁻²
 2.04047 kg m s⁻²
 2.10424 kg m s⁻²
    2.17 kg m s⁻²
 2.23781 kg m s⁻²
 2.30774 kg m s⁻²
 2.37986 kg m s⁻²
 2.45423 kg m s⁻²

julia> plot(1:length(sol[:]),sol[:])
ERROR: MethodError: no method matching isless(::Float64, ::SIUnits.SIQuantity{Float64,1,1,-2,0,0,0,0,0,0})
Closest candidates are:
  isless(::Float64, ::Float64) at float.jl:281
  isless(::AbstractFloat, ::AbstractFloat) at operators.jl:35
  isless(::Real, ::AbstractFloat) at operators.jl:36
  ...
 in expand_extrema!(::Plots.Extrema, ::SIUnits.SIQuantity{Float64,1,1,-2,0,0,0,0,0,0}) at /home/crackauc/.julia/v0.5/Plots/src/axes.jl:216
 in expand_extrema!(::Plots.Axis, ::Array{SIUnits.SIQuantity{Float64,1,1,-2,0,0,0,0,0,0},1}) at /home/crackauc/.julia/v0.5/Plots/src/axes.jl:239
 in expand_extrema!(::Plots.Subplot{Plots.GRBackend}, ::Dict{Symbol,Any}) at /home/crackauc/.julia/v0.5/Plots/src/axes.jl:255
 in _expand_subplot_extrema(::Plots.Subplot{Plots.GRBackend}, ::Dict{Symbol,Any}, ::Symbol) at /home/crackauc/.julia/v0.5/Plots/src/pipeline.jl:351
 in _process_seriesrecipe(::Plots.Plot{Plots.GRBackend}, ::Dict{Symbol,Any}) at /home/crackauc/.julia/v0.5/Plots/src/pipeline.jl:381
 in _plot!(::Plots.Plot{Plots.GRBackend}, ::Dict{Symbol,Any}, ::Tuple{UnitRange{Int64},Array{SIUnits.SIQuantity{Float64,1,1,-2,0,0,0,0,0,0},1}}) at /home/crackauc/.julia/v0.5/Plots/src/plot.jl:204
 in #plot#232(::Array{Any,1}, ::Function, ::UnitRange{Int64}, ::Vararg{Any,N}) at /home/crackauc/.julia/v0.5/Plots/src/plot.jl:52
 in plot(::UnitRange{Int64}, ::Array{SIUnits.SIQuantity{Float64,1,1,-2,0,0,0,0,0,0},1}, ::Vararg{Array{SIUnits.SIQuantity{Float64,1,1,-2,0,0,0,0,0,0},1},N}) at /home/crackauc/.julia/v0.5/Plots/src/plot.jl:46
 in eval_user_input(::Any, ::Base.REPL.REPLBackend) at ./REPL.jl:64
 in macro expansion at ./REPL.jl:95 [inlined]
 in (::Base.REPL.##3#4{Base.REPL.REPLBackend})() at ./event.jl:46

However, if you strip the values of their units

julia> plot(map((x)->x.val,sol[:]),sol.t) 

This works. (If you find a way to type check this and strip the units without adding the dependency, I'd be interested in something similar).

[tbreloff]

Can't you just add type recipes for this?

[ChrisRackauckas]

Oh true, didn't think about that.

[ChrisRackauckas]

Hey, I got the basic recipe together:

@recipe function f{ND,N,m,kg,s,A,K,mol,cd,rad,sr}(::Type{Array{SIUnits.SIQuantity{N,m,kg,s,A,K,mol,cd,rad,sr},ND}},x::Array{SIUnits.SIQuantity{N,m,kg,s,A,K,mol,cd,rad,sr},ND})
 map((y)->y.val,x)
end

However, I am wondering how I would add the axis to it. I can get a string for the units using SIUnits.unit(u[1]), so I was wondering how the recipe could pass that on as the guide for the position it's in. For example:

using SIUnits.ShortUnits
u = [1.0N 1.0N
     1.0N 1.2N
     1.5N 1.7N]

x = [1 1
     2 2
     3 3]

plot(x,u) # Works on all backends

I would like to have SIUnits.unit(u[1]) (which returns "kg m s^-2") to be the yguide (but if u and x were flipped, make it the xguide)

[ChrisRackauckas]

Superseded by #460.