Is there a functionality in Julia that's similar to R's negative indexing? In R, the code would be similar to:
x = 1:10
inds = c(1, 5, 7)
x[-inds]
[1] 2 3 4 6 8 9 10
I've found this to be extremely useful in numerous situations, especially for things such as sampling indices to create a testing/training set, but also for subindexing an array to exclude certain rows. So I am hoping there's something simple in Julia that can do the same.
Not a feature of the base language, but see for example the package here: https://github.com/mbauman/InvertedIndices.jl
This is similar to @Colin T Bower's answer and also only uses base Julia. Afraid it is not as elegant as your R example.
julia> minus(indx, x) = setdiff(1:length(x), indx)
minus (generic function with 1 method)
julia> x = collect(1:10)
10-element Array{Int64,1}:
1
2
3
4
5
6
7
8
9
10
julia> inds = [1, 5, 7]
3-element Array{Int64,1}:
1
5
7
julia> x[minus(inds, x)]
7-element Array{Int64,1}:
2
3
4
6
8
9
10