Is there a package for multidimensional ranges?

[aplavin]

Efficient rectangular grids: RectiGrids.jl, some discussion:

Regular grid

Depends on what functionality you need from the grid. The most bare-bones rectangular grid is Iterators.product(1:10, 1:100): it can be iterated or mapped over, but isn’t even an array. More extensive grids can be created with the RectiGrids.jl package. They are arrays, and even more, KeyedArrays, providing convenient lookup methods. (disclaimer: I’m the package author)

Depending on what you need in the end, you may also use map on top of the grid:

julia> using RectiGrids
julia> grid(1:3, 2:4)
2-dimensional KeyedArray(...) with keys:
↓   3-element UnitRange{Int64}
→   3-element UnitRange{Int64}
And data, 3×3 RectiGrids.RectiGridArr{...}:
      (2)        (3)        (4)
 (1)     (1, 2)     (1, 3)     (1, 4)
 (2)     (2, 2)     (2, 3)     (2, 4)
 (3)     (3, 2)     (3, 3)     (3, 4)

# similar to rectangulardomain() from RootsAndPoles, but better:
# remains a multidimensional array, not a flat vector
julia> map(t -> complex(t...), grid(1:3, 2:4))
2-dimensional KeyedArray(...) with keys:
↓   3-element UnitRange{Int64}
→   3-element UnitRange{Int64}
And data, 3×3 Matrix{Complex{Int64}}:
      (2)     (3)     (4)
 (1)   1+2im   1+3im   1+4im
 (2)   2+2im   2+3im   2+4im
 (3)   3+2im   3+3im   3+4im

# mapview() instead of map() avoids materializing the whole array:
julia> using FlexiMaps
julia> mapview(t -> complex(t...), grid(1:3, 2:4))
3×3 FlexiMaps.MappedArray{...}:
 1+2im  1+3im  1+4im
 2+2im  2+3im  2+4im
 3+2im  3+3im  3+4im