y=: a.{~ (a.i.'A')+i.4 5
m=: 3 1 0 2 1
m}y
PGCNJ
n=: 0 2 1 1 3
n}y
ALHIT
(m,:n) 4 : 'x}y'"1 _ y
PGCNJ
ALHIT
That is the nature of operator (adverbial or conjunctival) arguments:
you can not slice and dice them with other operators.
Use of explicit definition overcomes this flaw.
----- Original Message -----
From: "R.E. Boss" <[email protected]>
Date: Sunday, April 11, 2010 8:44
Subject: [Jprogramming] Amend
To: 'Programming forum' <[email protected]>
> In the vocabulary
> http://www.jsoftware.com/help/dictionary/d530n.htm the
> following example is given:
>
> y=: a.{~(a.i.'A')+i.4 5
> m=: 3 1 0 2 1
> y;m;m}y
> +-----+---------+-----+
> |ABCDE|3 1 0 2 1|PGCNJ|
> |FGHIJ|
> | |
> |KLMNO|
> | |
> |PQRST|
> | |
> +-----+---------+-----+
>
> But what if n=: 0 2 1 1 3 and I want (n,:m) } y ?
>
> (n,:m)}y
> |rank error
> | (n,:m)}y
>
> I could do
>
> (n,:m) } ,:"1~y
> ALHIT
> PGCNJ
>
> but that is neither elegant nor efficient.
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