Re: [Bug-apl] The Dyalog ⌸ operator

[Christian Robert]

where are you taking the definition of various functions like ?

power operator ?

dieresis jot ? like: (⊂⍤1) z,⍪z  (I really don't know what it is doing)

I see no references anywhere on the web. None in apl2 manual, none in Dyalog 
manual.

how can I learn thoses ...  without a manual and/or some examples ?


Xtian.



On 2016-04-26 23:02, Elias Mårtenson wrote:
> I was reading about the Dyalog "key" operator ⌸. It's certainly a useful 
> function, and something that should probably be added to GNU APL, in my opinion.
>
> As always when thinking about useful additions to GNU APL, I wanted to try to 
> do some things that ⌸ can do, without having access to it.
>
> So, I wanted to simply take a string of characters, and create a list of each 
> character and the number of occurrences of each character in that string. My 
> solution works, but feels clumsy:
>
> *       { ⊃{(↑⍵) (↑⍴⍵)}¨(⎕UCS v) ⊂ v←⍵[⍋⍵] } "abcfoobat"*
> ┏→━━━━┓
> ↓'a' 2┃
> ┃'b' 2┃
> ┃'c' 1┃
> ┃'f' 1┃
> ┃'o' 2┃
> ┃'t' 1┃
> ┗━━━━━┛
>
> Can anyone improve this? In particular, can it be improved to the point of 
> convincing me that ⌸ is not needed?
>
> Regards,
> Elias