Can't use tuple of `UInt` as index

General Usage
1

Is this expected behavior?

julia> idx = UInt(3); A = rand(4); A[idx]
0.10882052381690266

julia> idx = (UInt(3), UInt(1)); A = rand(4, 5); A[idx]
ERROR: ArgumentError: invalid index: (0x0000000000000003, 0x0000000000000001) of type Tuple{UInt64,UInt64}
Stacktrace:
 [1] to_index(::Tuple{UInt64,UInt64}) at .\indices.jl:297
 [2] to_index(::Array{Float64,2}, ::Tuple{UInt64,UInt64}) at .\indices.jl:274
 [3] to_indices at .\indices.jl:325 [inlined]
 [4] to_indices at .\indices.jl:322 [inlined]
 [5] getindex(::Array{Float64,2}, ::Tuple{UInt64,UInt64}) at .\abstractarray.jl:1060
 [6] top-level scope at none:1

I’m writing a function that I would like to work with with UInt or Int arrays as input, but this issue (and an analogous one when using get(A, idx, 0)) is getting in the way.

2

You can either splat or use a CartesianIndex if you want to index a multidimensional array.

julia> A[idx...]
0.8201224060592813

julia> A[CartesianIndex(idx)]
0.8201224060592813

julia> get(A, CartesianIndex(idx), 0)
0.8201224060592813
1 Like
3

Splat doesn’t work in get(), but CartesianIndex() does. Thank you.

4

This has been solved, I just wanted to point out that it is unrelated to UInt vs Int. You simply cannot index with tuples like that, so the same thing will happen here:

jl> idx = (3, 1); A[idx]
ERROR: ArgumentError: invalid index: (3, 1) of type Tuple{Int64,Int64}
5

You can use get() like that with no problem, hence my issue.