Download CSV from DataFrame in Pluto


Is there a better way to generate a downloadable CSV file from a dataframe in Pluto/PlutoUI than using CSV.write with take! like this?

df = DataFrame(a=[1,2],b=["a","b"])
DownloadButton(take!(CSV.write(IOBuffer(),df;delim=';')), "data.csv")

How do you define β€œbetter”? If you mean not using CSV.jl then you can do:

show(io, MIME("text/csv"), df)

but it will be less flexible than CSV.write regarding options.

1 Like

Sorry, I meant simpler, like maybe using a single method to get a β€œCSV string” from a dataframe.

Something like this :

DownloadButton(CSV.write_to_string(df;delim=';'), "data.csv")

In the PlutoUI DownloadButton documentation, I found the example for Json generation quite nice :

DownloadButton(JSON.json(Dict("name" => "merlijn", "can_cook" => true)), "staff.json")

Does this do what you want?

julia> using CSV

julia> using DataFrames

julia> df = DataFrame(a=1:2, b=3:4)
2Γ—2 DataFrame
 Row β”‚ a      b
     β”‚ Int64  Int64
   1 β”‚     1      3
   2 β”‚     2      4

julia> sprint(CSV.write, df)

Yes, thank you, that’s a good simple solution.

DownloadButton(sprint(CSV.write, df), "data.csv")

Otherwise, it’s about the same size as the initial solution when additional parameters are needed :

# with sprint
DownloadButton(sprint((i,d) -> CSV.write(i,d;delim=';'),df), "data.csv")
# with take!
DownloadButton(take!(CSV.write(IOBuffer(),df;delim=';')), "data.csv")