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Comment by sida | Hacker News Reader

As weird as it sounds, the only thing that stops me from trying Julia is 1 indexing

IMO, Julia is good enough that you might not notice. you can use constructions like `for i in axes(V)` that will automatically give you the indexes, or `V[begin:begin+2]` to get the first 2 elements. Also higher order functions eg. `map` (and broadcasting) mean that you will rarely be manually working with indexes.

You still need to access indexes if you're working with arrays though, which is a very common data structure.

That's not so obvious, the abstractions for multi-dimensional indexing are better than (I think) you're imagining.

Here's a nice recent example: a new reverse!(A; dims) function, which is fast and works on arrays with any number of dimensions. And is completely indifferent to where the indices start:

https://github.com/JuliaLang/julia/pull/37367/files#diff-eb9...

I'm not 100% sure what I'm looking at, but that seems to be related to reversing arrays/matrices, not accessing arrays through indexes.

Maybe less readable than I remembered, sorry! But these `CartesianIndex` things are how you index multi-dimensional arrays.

If by indexing you only mean adding offsets to pointers with your bare hands, this is possible but discouraged. Because you'll produce a buggier and less general version of exactly what already exists. In this case, reversing an N-dimensional array, along any M of its axes, with arbitrary offsets -- there are a lot of ways to get that wrong.

What I mean is something like this:

    # one dimensional
    a = [1, 2, 3]
    # prints the number 1 @ index 0
    print(a[0])
    
    # multi-dimensional
    b = [[1, 2, 3], [4, 5, 6]]
    # prints the number 4 @ index (1, 0)
    print(b[1][0])

In Julia these indexes would start from 1. It doesn't seem like `CartesianIndex` solves this, since looking at some examples you still have to specify array indexes (Which start from 1): https://docs.julialang.org/en/v1/base/arrays/#Base.Iterators...

OK, I thought you were advocating zero based on complicated index calculations for some algorithm, with mod & div, which is what I was trying to say could be abstracted away. The literal syntax `a=[1,2,3]` makes a one-dimensional `Array{Int,1}` whose first element is indeed `a[1]`. (`b` is an array of arrays, while `c = [1 2 3; 4 5 6]` is an honest 2-dimensional array.)

Because you believe that you can't get used to a different convention? It gets brought up a lot that for array offsets, zero based is more natural. In my experience, the amount of index calculations you need in Julia is minimal anyway because there are really nice abstractions for n-dimensional indexing.

0-based indexing is an artefact of pointer math. Modern languages don't treat arrays as a pointers to their first element. So, it is still with us only because almost no language designer decided to challenge existing convention.

I see 1-indexing as an artifact of a lot of linear algebra texts, whereas 0-indexing is more popular in analysis. Julia just wants it to be easier to directly copy formulas from publications.

I also think it’s blurry as to whether mathematicians and programmers see indexing numbers as merely indices or richer numbers.

The beautiful thing of having polyglot experience, since the days when C was just another language trying to get users, is not being put down by minutia like that.

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