I have 2 arrays of Dict containing from and to items, both of type ZonedDateTime (although for our example they could be integers, doesn’t matter). They are basically 2 arrays of ranges. What would be the simplest/the most efficient way to determine whether they intersect? Thank you,

Intersect in which sense? Have the same keys? Have the same values? Have the same pairs of key and value? The intersection is about the Dicts having the same keys/values, or the keys/values itself intersecting with the keys/values of another Dict?

Let’s assume “from” and “to” are integers (so that’s easier for me to write an example). A = [Dict(“from”=>1, “to”=>20), Dict(“from”=>51, “to”=>100)] B = [Dict(“from”=>21, “to”=>50), Dict(“from”=>99, “to”=>105)] In this case, they do intersect with 2 values, 99 and 100. In another example: C = …

Why are you using Dicts for the ranges? Why not use UnitRange{Int64} (or in your real case UnitRange{ZonedDateTime}). The ranges inside the same array are mutually exclusive (i.e., do not share any numbers?) the arrays are sorted? All of this is relevant for knowing what is the most efficient algor…

If you can do not mind use other structures than Dict (which is rather inefficient in this case), you can use nice Intervals.jl package. Something like this function combineintervals(A, B) res = Vector{eltype(A)}() for a in A, b in B c = intersect(a, b) isempty(c) || push!(r…

I had some time at lunch; and always nice to learn never-heard packages like Intervals. struct FromTo from to function FromTo(f,t) @assert t>=f "`To` has to be >= `From`" new(f,t) end end struct FromToCollections l::Array{FromTo} end A = FromToCollections([From…

Also, intersect is already defined by Base because Base already has UnitRanges. Sincerely, unless there is a good reason, this seems to be reinventing the wheel. Often an interval is just two values that have ordering functions defined for them, and there is a lot of code that already works over bo…

Intersect of 2 arrays

New to Julia

Skoffer January 15, 2021, 4:08pm 3

Can you provide an MWE, please? It would be much easier if you give a small example of what you have and what you are trying to achieve.

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Intersect of 2 arrays

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