Export dataframe to html file

New to Julia
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1

Hi there
I have read a csv file into Julia, as a dataframe, with some columns of type string, some of type integer, and others of type float. I would like to save, or export or write this dataframe as an html file. What is the simplest procedure?

2

PrettyTables has an HTML backend

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3

I will have a look at this package. Thank you.

4

I have this MWE.

using DataFrames
df = DataFrame(Name=["Andrew", "Barbara"],Id=[1,2],Exam_1=[3.5,7.0])
using PrettyTables
pt = pretty_table(df; backend = Val(:html), alignment=:c)

When run in a notebook, this gives me a really prettily formatted html output in a new cell, whereas when run in a plain Julia prompt it gives what I assume is the corresponding code for the html file. My problem now is how to save this pt object to an html file, preserving all the beautiful formatting. I have tried:

save("output.html", pt)

but it prints the error:

Error encountered while save FileIO.File{FileIO.DataFormat{:HTML}, String}("output.html").

Fatal error:
ERROR: ArgumentError: Argument does not support conversion to HTML.
...

How do I concretely export or save the a PrettyTable pt object formatted from the html back-end?

5

There is an optional first argument to the pretty_table function which is the io::IO (input/output) argument. (See the first couple paragraphs of the pretty_table documentation.)

The following is untested but should work:

open("output.html", "w") do io
    pretty_table(io, df; backend = Val(:html), alignment=:c)
end

The open function with a do block is the safe way to open and close I/O streams in Julia. (It will close the stream even if the write fails with an error.)

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6

Thanks Nils and Nathan. Nathan’s chunk of code did work. Thanks again!

7

The same in plain DataFrames.jl:

julia> using DataFrames

julia> df = DataFrame(x=1:2, y=["a", "b"],z = [1.5, 2.5])
2×3 DataFrame
 Row │ x      y       z
     │ Int64  String  Float64
─────┼────────────────────────
   1 │     1  a           1.5
   2 │     2  b           2.5

julia> open("output.html", "w") do io
           show(io, MIME("text/html"), df)
       end
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