What is the purpose of the double-enclose ⊂⊂⍬ ?
My understanding was that (⊂⊂x)≡⊂x for all x?
Regards,
Elias
On 3 March 2016 at 16:05, Jay Foad <jay.f...@gmail.com> wrote:
> Right. Here's a variation on Elias's solution that gets IOTA ⍬ right,
> but doesn't handle the singleton cases correctly!
>
> IOTA ← {⊃∘.,/(⍳¨⍵),⊂⊂⍬}
>
> On 3 March 2016 at 01:08, Nick Lobachevsky <ibeam2...@gmail.com> wrote:
> > There is at least one other degenerate case, namely the "legacy"
> > singleton, or one element vector. With a scalar argument, monadic
> > iota returns a result depth one. With a vector argument, iota returns
> > a result depth two. Except when there is only one element.
> >
> > ≡⍳⍳0 ⍝ can't find zilde
> > 2
> > ≡⍳⍳1 ⍝ singleton vector case returns result depth one
> > 1
> > ≡⍳,1
> > 1
> > ≡⍳,2
> > 1
> > ≡⍳,42
> > 1
> > ≡⍳(15⍴1)⍴1 ⍝ matrix singleton thankfully fails
> > RANK ERROR
> > ≡⍳⍳2
> > 2
>
