Hello, I need to construct a DataFrame similar to: df=DataFrame([ String, String, String, ... ], [ :cod_1, :cod_2, :cod_3, cod_... ], 0); where the number of String is huge. So, by supposing that this number is N, how to co…

I’m not sure, if I missed something, but this is valid code: julia> n = 7 7 julia> DataFrame([String for k in 1:n], [Symbol("cod_$k") for k in 1:n], 0) 0×7 DataFrame

[image] zweiglimmergneis: DataFrame([String for k in 1:n], [Symbol(“cod_$k”) for k in 1:n], 0) Thanks ! It works ! Nevertheless, how to use it when we need to have Date and String. More precisely, this bad code does not work: DataFrame([Date, String for k in 1:2], [:val_date…

For passing the Vector{DataType}, vcat(Date, fill(String, 2)) # Example [Date, String, String] You can use vcat for the names as well.

Yes, and eventually think of using the broadcast feature for the column names. julia> using DataFrames, Dates julia> n = 7 7 julia> makecol(k) = Symbol("cod_", k) makecol (generic function with 1 method) julia> df = DataFrame([Date, fill(String, n)...], [:valdate, makecol.(…

For a more general way to do this, you can create an “empty” DataFrame with the schema that you want and then just push! Dicts or Named Tuples to add observations to it. I have done this with fair amounts of success when the creation of the DataFrame is less trivial.

How to construct a DataFrame with a loop?

General Usage

kristoffer.carlsson April 9, 2019, 2:10pm 2

Please see PSA: how to quote code with backticks (and update your post accordingly).

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How to construct a DataFrame with a loop?

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