Streamgraph

#Array methods
streamgraph(x::AbstractVector{String}, y::AbstractVector{<:Union{Missing, Real}}, group::AbstractVector)
streamgraph(x::AbstractVector{<:Union{Missing, Real}}, y::AbstractVector{<:Union{Missing, Real}}, group::AbstractVector)

#DataFrame methods
streamgraph(df::AbstractDataFrame, x::Symbol, y::Symbol, group::Symbol)

legend::Bool = false
kwargs... #modifies top-level EChart properties

using ECharts, DataFrames, CSV
s_df = CSV.read(Pkg.dir("ECharts", "exampledata/streamdata.csv"), types=[String, Float64, String])
sg = streamgraph(s_df[:date], s_df[:value], s_df[:key], legend = true)
#alternate: sg = streamgraph(s_df, :date, :value, :key, legend = true)