I want to check if my DataFrame contains all of the columns I specified. Of course I can do it with the code below, but I have the feeling it should be possible in one line.
using DataFrames
bools = Array{Bool}([])
df = DataFrame(A=[1,2], B=[3,4], C=[5,6])
for name in ["A", "B"]
push!(bools, name ∈ names(df))
end
false ∉ bools
I found it. The ⊆ operator can be used to check if one Array is a subset of another:
# "⊆" can be typed by \subseteq<tab>
julia> ["A", "B"] ⊆ names(df)
true
julia> issubset(["A", "B"], names(df))
true
potentially useful as well are ⊈ (not a subset), ⊊ (subset but not equal) or the ⊇ (super set) variants of these operators.
# "⊈" can be typed by \nsubseteq<tab>
julia> ["A", "D"] ⊈ names(df)
true
# "⊊" can be typed by \subsetneq<tab>
julia> ["A", "B", "C"] ⊊ names(df)
false
julia> ["A", "B"] ⊊ names(df)
true
# "⊇" can be typed by \supseteq<tab>
julia> ["A", "B", "C", "D"] ⊇ names(df)
true