I just observed the following on v1.4 (so apologies if it is gone on v1.5). julia> x = [ rand(0:9, 2) for a = 1:3 ] 3-element Array{Array{Int64,1},1}: [3, 8] [2, 4] [3, 1] julia> x[1,1] 2-element Array{Int64,1}: 3 8 julia> x[1] 2-element Array{Int64,1}: 3 8 Why does x[1,1] work at all, an…

There is a short note at the end of this chapter: https://docs.julialang.org/en/v1/manual/arrays/#Omitted-and-extra-indices You can in your example do: julia> x[1,1,1,1,1] 2-element Array{Int64,1}: 7 3

[image] colintbowers: And given that it does work, why does x[1,2] not work? It can’t work for x[1,2] since that would require x to be a matrix with at least two columns, which it isn’t. The fact that you can append arbitrary numbers of 1s to the indices is indeed a bit confusing, given that …

[image] DNF: The fact that you can append arbitrary numbers of 1 s to the indices is indeed a bit confusing, given that there is a clear separation between vectors and matrices. Quoted from the docs: Similarly, more than N indices may be provided if all the indices beyond the dimensionality…

Yes, the docs are clear enough, but it clashes with my explanation when I try to tell people that vectors are different from an Nx1 matrix, saying that there is no second dimension at all. [image] oheil: I would expect to have the multidimensional array as the base for everything, in other word…

[image] oheil: Confusing? Only for mathematicians. This is a design choice that was taken very early in Julia and cannot be changed now as it would break the API, but with hindsight it is not so obvious that this was the best solution. These things will be with us for a while, and may not be…

Relax, nothing I want to change. It was only meant for the point of view on some things and what could confuse and what not. Of course, this is indivual taste and my taste of the point if view is first general multidimensional array and after that specialized implementations. So I am not confused ab…

[image] oheil: Of course, this is indivual taste and my taste of the point if view is first general multidimensional array and after that specialized implementations. Since I spend so much time fuming over the lack of distinction between vectors and matrices in Matlab (it is my day job), I’m …

[image] DNF: What does this mean, and is it different from Julia, and similar to Matlab? This I can’t answer as I do not have any experience with matlab. [image] DNF: Since I spend so much time fuming over the lack of distinction between vectors and matrices in Matlab (it is my day job),…

[image] oheil: as @Tamas_Papp pointed out, it doesn’t make sense for Julia to have this type of academic stringency I think you misunderstood my post: I am arguing that supporting the trailing 1s makes little sense with how Julia works currently. It is a historical artifact, it did make some …

Thanks for your reply. We were perhaps talking about different things (though I’m not completely certain.) [image] oheil: And now I learned that Matlab seems not to separate 1-dim Arrays (vectors) from 2-dim arrays (matrices), may be it is not needed for Matlab to distinguish because the implem…

[image] Tamas_Papp: I think you misunderstood my post: I am arguing that supporting the trailing 1 s makes little sense with how Julia works currently. It is a historical artifact, it did make some algorithms easier initially. I see. But still it isn’t a bug and it is somehow well documented. …

Why is the following behaviour not a bug?

General Usage

Tamas_Papp October 28, 2020, 5:39pm 14

I don’t know where the threshold will be between revising minor warts (which not everyone considers warts, BTW) and keeping compatibility, but I suspect it will lean toward the latter. Cf

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Why is the following behaviour not a bug?

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