📂Julia

Renaming Column Names of a DataFrame in Julia

Overview

To rename columns, you can use the rename!() function¹.

You can rename them all at once by providing a list of strings, or individually.

Code

using DataFrames

df = DataFrame(rand(1:9, 10, 3), :auto)
rename!(df, ["X", "Y", "Z"])
rename!(df, :X => :A)

When executed, it first creates the following dataframe:

julia> df = DataFrame(rand(1:9, 10, 3), :auto)
10×3 DataFrame
 Row │ x1     x2     x3    
     │ Int64  Int64  Int64 
─────┼─────────────────────
   1 │     2      3      6
   2 │     9      2      4
   3 │     3      3      4
   4 │     3      3      3
   5 │     9      1      6
   6 │     3      1      5
   7 │     4      8      4
   8 │     9      8      4
   9 │     4      6      1
  10 │     1      9      7

Renaming All at Once

julia> rename!(df, ["X", "Y", "Z"])
10×3 DataFrame
 Row │ X      Y      Z     
     │ Int64  Int64  Int64 
─────┼─────────────────────
   1 │     2      3      6
   2 │     9      2      4
   3 │     3      3      4
   4 │     3      3      3
   5 │     9      1      6
   6 │     3      1      5
   7 │     4      8      4
   8 │     9      8      4
   9 │     4      6      1
  10 │     1      9      7

Just provide a list of strings.

Renaming One by One

julia> rename!(df, :X => :A)
10×3 DataFrame
 Row │ A      Y      Z     
     │ Int64  Int64  Int64 
─────┼─────────────────────
   1 │     2      3      6
   2 │     9      2      4
   3 │     3      3      4
   4 │     3      3      3
   5 │     9      1      6
   6 │     3      1      5
   7 │     4      8      4
   8 │     9      8      4
   9 │     4      6      1
  10 │     1      9      7

This method, which is rarely seen in other languages, involves prefixing column names with : and mapping them with =>. In Julia, a variable that starts with : is a Symbol.

Environment

• OS: Windows
• julia: v1.6.2