Just to make sure that we're on the same page: you say that your suggestion
actually doesn't work to construct a Matrix{Vector3}?
or is does [[a,a,a]' ; [a,a,a]'] lead to different results than [b ; b]?
I just tried it, [b ; b] on my 4 days old master yields Matrix{Vector3}.
(with b = Array(Vector3{Int}, 1, 3), as it's currently impossible to create
b differently)
2015-02-26 1:39 GMT+01:00 Josh Langsfeld <[email protected]>:
> In general I think you are making good points. Different parallel syntaxes
> for constructing with and without flattening would be a nice feature.
>
> On Wed, Feb 25, 2015 at 6:46 PM, Simon Danisch <[email protected]> wrote:
>
>> So what do I expect from your case?
>> [[a,a,a]' ; [a,a,a]']
>> b = [a,a,a]' => some array, which looks comparable to Case 2
>> [b ; b] -> independent of b's shape, this should result in
>> Array{eltype(b)} and not Array{typeof(b)}, from what I learned in Case 2.
>> Otherwise this is quite confusing, as concatenating would also depend on
>> the shape, which makes it hard to predict, when something concatenates or
>> just constructs.
>>
>
> In this case, [b ; b] does indeed always have type Array{eltype(b)} and
> not Array{typeof(b)} (unless typeof(b) == Number).
>
>
>>
>> 2015-02-26 0:10 GMT+01:00 Josh Langsfeld <[email protected]>:
>>
>>> Assuming transposing works, you could do [[a,a,a]' ; [a,a,a]'] which
>>> isn't entirely horrible
>>>
>>> On Wednesday, February 25, 2015 at 5:50:04 PM UTC-5, Simon Danisch wrote:
>>>>
>>>> Okay... So how do I realize:
>>>> a = vec3(...)
>>>> [ a a a ; a a a]
>>>>
>>>> Well, all I think is, that arrays of arrays get treated like second
>>>> class citizens, as it is harder to work with them in the same way, as it
>>>> would be possible with concatenating ;)
>>>> This is especially relevant with FixedSizeArrays coming up, as they
>>>> allow for tightly packed array of arrays.
>>>> What I mean becomes obvious, if you look at the number of constructors:
>>>> [a,b,c] for non concatenating
>>>> vs
>>>> [a;b;c;], [a b c], [a b c; a b c] (+ some variations) for concatenation
>>>>
>>>>
>>>> 2015-02-25 23:24 GMT+01:00 Jeff Bezanson <[email protected]>:
>>>>
>>>>> Transposing [vec1, vec2, vec3] will absolutely work. I think the issue
>>>>> you saw with it was specific to ImmutableArrays. I don't know why they
>>>>> have that behavior.
>>>>>
>>>>> On Wed, Feb 25, 2015 at 5:21 PM, Simon Danisch <[email protected]>
>>>>> wrote:
>>>>> > I mean, my whole busyness is about constructing matrices of
>>>>> Vec2/3/4, which
>>>>> > inherit from DenseArray.
>>>>> > So I'm basically forced, if I'm not missing something, to do quite a
>>>>> bit of
>>>>> > work to get my [vec1 vec2 vec3] going.
>>>>> > Especially, as transpose([vec1, vec2, vec3]) doesn't seem to work,
>>>>> bug or
>>>>> > not isn't known to me.
>>>>> >
>>>>> > 2015-02-25 23:18 GMT+01:00 Simon Danisch <[email protected]>:
>>>>> >>
>>>>> >> Well, the issue raised here was, how do you realize non concatening
>>>>> [a b
>>>>> >> c]? This seems impossible now, even though that there are quite a
>>>>> few use
>>>>> >> cases for it...
>>>>> >>
>>>>> >> 2015-02-25 23:13 GMT+01:00 Stefan Karpinski <[email protected]>:
>>>>> >>>
>>>>> >>> I actually think the plan of [a,b,c] for construction without
>>>>> >>> concatenation and [a;b;c] and [a b c] for concatenation is pretty
>>>>> good. I no
>>>>> >>> longer feel that there's any need for a new bracket like [| |].
>>>>> The thing
>>>>> >>> that clicked for me is that [a;] isn't really concatenation at all
>>>>> anyway.
>>>>> >>>
>>>>> >>> On Wed, Feb 25, 2015 at 4:58 PM, Simon Danisch <[email protected]>
>>>>>
>>>>> >>> wrote:
>>>>> >>>>
>>>>> >>>> As Julia was the first language to introduce me to this kind of
>>>>> >>>> constructs, I'm not sure about your used terms.
>>>>> >>>> Concatenate for me would firstly mean, to just connect elements
>>>>> (that's
>>>>> >>>> at least what the German translation suggests), which I would
>>>>> apply to the
>>>>> >>>> process of putting the elements together into one array. The
>>>>> elements in my
>>>>> >>>> case are the Vectors.
>>>>> >>>> You seem to use it as synonymous with concatenation + flattening
>>>>> >>>> (sticking to the function names I guess).
>>>>> >>>> I'd say [a,b] is supposed to concatenate, but shouldn't flatten,
>>>>> right?
>>>>> >>>> So yes, different syntax for concatenating, and
>>>>> concatenating+flattening
>>>>> >>>> would make this case much, much clearer.
>>>>> >>>> Then it's not this fuzzy magic thing, that sometimes happens and
>>>>> >>>> sometimes not and both clearly encapsulates a concept and use the
>>>>> same basic
>>>>> >>>> syntax.
>>>>> >>>> So:
>>>>> >>>> [vec, vec] => [vec, vec] # With optional typing, ensuring that
>>>>> you don't
>>>>> >>>> end up with Any[]
>>>>> >>>> [vec vec] => [vec vec] # With optional typing, ensuring that you
>>>>> don't
>>>>> >>>> end up with Any[]
>>>>> >>>>
>>>>> >>>> [| vec, vec |] => [el1, el2, el3, el4, ...]# With optional typing,
>>>>> >>>> ensuring that you don't end up with Any[]
>>>>> >>>> [| vec vec |] => [el el2 ; el3 el4]# With optional typing,
>>>>> ensuring
>>>>> >>>> that you don't end up with Any[]
>>>>> >>>>
>>>>> >>>> I do think, that this is very clear and consistent and doesn't
>>>>> leave
>>>>> >>>> anything in doubt!
>>>>> >>>>
>>>>> >>>>
>>>>> >>>> Am Mittwoch, 25. Februar 2015 19:00:01 UTC+1 schrieb Simon
>>>>> Danisch:
>>>>> >>>>>
>>>>> >>>>> Hi there,
>>>>> >>>>> I thought default concatenation was deprecated, to make it
>>>>> easier to
>>>>> >>>>> create arrays of arrays... But it became rather impossible and
>>>>> confusing in
>>>>> >>>>> the horizontal case, from what I see.
>>>>> >>>>> Is there really not a single method left from the few ways in
>>>>> 0.35 of
>>>>> >>>>> creating a horizontal vector of vectors?
>>>>> >>>>> 0.4:
>>>>> >>>>>
>>>>> >>>>> https://gist.github.com/SimonDanisch/6972c1c090c608738e83#file-
>>>>> cat0-4-jl
>>>>> >>>>> 0.3.5:
>>>>> >>>>>
>>>>> >>>>> https://gist.github.com/SimonDanisch/058ef76b2583c620b667#file-
>>>>> cat3-5-jl
>>>>> >>>>>
>>>>> >>>>> Am I missing something, or is this a bug?!
>>>>> >>>>>
>>>>> >>>>> Best,
>>>>> >>>>> Simon
>>>>> >>>
>>>>> >>>
>>>>> >>
>>>>> >
>>>>>
>>>>
>>>>
>>
>
