Hello, when I use the example from GitHub - JuliaPlots/StatsPlots.jl: Statistical plotting recipes for Plots.jl
using DataFrames, StatsPlots
df = DataFrame(a = 1:10, b = 10 .* rand(10), c = 10 .* rand(10))
@df df plot(:a, cols(2:3), colour = [:red :blue])
I get the error ArgumentError: unsupported symbol b passed to label
Does anyone know what I am missing?