Re: Output variants for pick and index operators

[Dr . Jürgen Sauermann]

    Hi Hans-Peter,
      
      see below. Note that ⌷ and ⊃ give different
      results
      in GNU APL and also in IBM APL2 (PC version).
    
    Best Regards,
    Jürgen

On 3/14/23 10:12 PM, Hans-Peter Sorge wrote:

>       
>       Hi Jürgen,
>       
>       looks like I have plenty of time,
>       however, it's being usefully invested:-)
>       
>       (SVN 1660)
>       
>       This displays as expected.
>           X (8⎕CR  X ←1 2 3
>           ⊃¨⊂'A' 'CD' 'EF') 
>          A CD EF   ┌→──────────┐  
>                    │A ┌→─┐ ┌→─┐│  
>                    │  │CD│ │EF││  
>                    │  └──┘ └──┘│  
>                    └ϵ──────────┘  
>         
>       
    Same in APL2. Note that putting X and (8⎕CR ... on
    the same line adds one level of indentation.
    
>  A..CD  OK, CD...EF one space
>         more.
>               X
>           (8⎕CR  X ←1 2 3 ⌷¨⊂'A' 'CD' 'EF') 
>          A  CD   EF    ┌→──────────────┐  
>                        │A ┌────┐ ┌────┐│  
>                        │  │┌→─┐│ │┌→─┐││  
>                        │  ││CD││ ││EF│││  
>                        │  │└──┘│ │└──┘││  
>                        │  └ϵ───┘ └ϵ───┘│  
>                        └ϵϵ─────────────┘ 
>         
>       
    Same in APL2.
>  
>       In Ref to "V" from previous
>         conversations ...
>         
>         Display for "⊃" and "⌷" differ, the bare outputs are identical.
>         
>               X
>           (8⎕CR  X ←1 2 3 ⊃¨⊂V)             
>          A  1 2 3 4 5   0 0 0   ┌→────────────────────┐  
>                         0 0 0   │A ┌→────────┐ ┌→────┐│  
>                         0 0 0   │  │1 2 3 4 5│ ↓0 0 0││  
>                                 │  └─────────┘ │0 0 0││  
>                                 │              │0 0 0││  
>                                 │              └─────┘│  
>                                 └ϵ────────────────────┘  
>       
    Same in APL2.
>  Same layout as before
>               X
>           (8⎕CR  X ←1 2 3 ⌷¨⊂V) 
>          A  1 2 3 4 5   0 0 0    ┌→────────────────────────┐  
>                         0 0 0    │A ┌───────────┐ ┌───────┐│  
>                         0 0 0    │  │┌→────────┐│ │┌→────┐││  
>                                  │  ││1 2 3 4 5││ │↓0 0 0│││  
>                                  │  │└─────────┘│ ││0 0 0│││  
>                                  │  └ϵ──────────┘ ││0 0 0│││  
>                                  │                │└─────┘││  
>                                  │                └ϵ──────┘│  
>                                  └ϵϵ───────────────────────┘
>         
>       
    Same in APL2.
>  As a side note. 
>         The output has trailing space(s) included
>         3 spaces EF...1  OK? Should be 2 spaces?
>            X ←1 2 3
>           ⊃¨⊂'A' 'CD' 'EF' 
>               X 1 
>          A CD EF   1  
>       
>     
    I get 1 leading and trailing space: 
    
          Q ← ⍕ X ←1 2 3 ⊃¨⊂'A' 'CD' 'EF' ◊
        ((' '=ϵQ)/ϵQ)←'∘' ◊ Q
      ∘A∘CD∘EF∘
      
>  4 spaces EF....1 OK? Should be 2
>           spaces?
>              
>           X ←1 2 3 ⌷¨⊂'A' 'CD' 'EF' 
>               X 1 
>          A  CD   EF    1 
>         
>       
    I get2 trailing spaces:
    
          Q ← ⍕ X ←1 2 3 ⌷¨⊂'A' 'CD' 'EF' ◊
        ((' '=ϵQ)/ϵQ)←'∘' ◊ Q
      ∘A∘∘CD∘∘∘EF∘∘
       
>  Best Regards
>         Hans-Peter
>         
>