myd = DataFrame(a = 1:3, b = ["aba","saba","daba" ]) Now trying to find the position of :b elements in certain vector and make a new column out of it: myd = transform(myd, :b => (v -> findfirst(x -> x==v, ["saba","daba","myy","aba","oba"])) => :sort_order) I end up with column of nothing.

It’s because your function is wrongly specified: You check if x == v where x is an element in the vector v. You could do v2 = ["saba","daba","myy","aba","oba"] transform(myd, :b => v -> [findfirst(isequal(i), v) for i in v2]) To be more efficient, you should probably create a Dict{String, Int} t…

Finding the position in array

New to Julia

rafael.guerra February 14, 2022, 1:31pm 3

@Mastomaki, what result do you expect?

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Finding the position in array

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