Select colums by the value of rows

[chenr86]

Hello,

I want to select target colums with row values between an interval. For example, with df like below, I want to select colums with row values between [3, 5], which means that it should return :x1 :x2 :y1. How can I do that?

df = DataFrame(a=1, b=2, x1=3, x2=4, y1=5, y2=6)

[chenr86]

For someone interested on this topic, the solution can be:

df_filter = DataFrame()
for i in 1:size(df, 2)
    if 3 <= df[end, i] <= 5
        df_filter[!, "Plan$i"] = df[:, i]
    end
end
df_filter

[Jollywatt]

You could also select columns via a predicate like so:

julia> collect(df[1, :])
6-element Vector{Int64}:
 1
 2
 3
 4
 5
 6

julia> 3 .<= ans .<= 5
6-element BitVector:
 0
 0
 1
 1
 1
 0

julia> df[!, ans] # use ! to return a view; use : to copy
1×3 DataFrame
 Row │ x1     x2     y1
     │ Int64  Int64  Int64
─────┼─────────────────────
   1 │     3      4      5

[DataFrames]

use

df[:, [all(in(3:5), x) for x in eachcol(df)]]

[rafael.guerra]

Perhaps safer to not assume integers:

 df[:, [all(3 .≤ x .≤ 5) for x in eachcol(df)]]