Dataframe to csv with the index column

New to Julia
1

How to write a dataframe with the index column to a csv please? This is what I have put togeter but I am missing the index. (Btw, I dont even know if thats the best way. What I want, is to save a nested list of lists to a csv along with some identifier)

using CSV
using DataFrames

lis = [[1,2,3,4], [3], [5, 8]]
d = Dict( (i => [lis[i]] for i=1:length(lis)))
df = DataFrame(d)
df = DataFrame(Matrix(df)')
df = select(df, "x1" => "col_1")
CSV.write("df.csv", df, header=true)
2

A quick look at the docs and it seems like there isn’t a way to have the row number be printed. Just do

julia> insertcols!(df, 1, :Row => 1:nrow(df))
3×2 DataFrame
│ Row │ Row   │ col_1     │
│     │ Int64 │ Adjoint…  │
├─────┼───────┼───────────┤
│ 1   │ 1     │ [1 2 3 4] │
│ 2   │ 2     │ [3]       │
│ 3   │ 3     │ [5 8]     │

and it will save with a column Row.

But it sounds like you are having some trouble with DataFrames constructors. Maybe do this to create your data frame

julia> d = DataFrame(Row = 1:length(lis), Value = lis)
3×2 DataFrame
│ Row │ Row   │ Value        │
│     │ Int64 │ Array…       │
├─────┼───────┼──────────────┤
│ 1   │ 1     │ [1, 2, 3, 4] │
│ 2   │ 2     │ [3]          │
│ 3   │ 3     │ [5, 8]       │
3

Thanks so much"

4

Also note that you can transpose a data frame using permutedims. And calling a DataFrame constructor with a Matrix is deprecated. Use DataFrame(Matrix(df)', :auto).

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