'*' (I.,b)"_} a
Not just in this specific case but in general it is
better to use i.$y as the canonical indices rather
than {i.&.>$y . The latter takes orders of
magnitude more time and space for no extra benefit.
Of course if we are talking about just this specific
case, b{'-*' would do. :-) Anyway it would be
prudent to use non-atomic x in talking about x m}y
lest one is misled by properties that are absent
for more general x .
----- Original Message -----
From: Andrew Nikitin <[EMAIL PROTECTED]>
Date: Friday, July 21, 2006 11:18 am
Subject: [Jprogramming] RE: }
> Brewer, Andrew:
> >R.E.,
> >I've found { kind or useful for working with amend, but keeping
> the array
> >structure intact (maybe helpful for amend in-place?)
> >
> >For example:
> >
> > indexes =. , @ { @: (i.each) @ $
> > ] a =: 5 9 $ '-'
> > ] b =: ? ($a) $ 2
> > ] a =: '*' ( (,b) # indexes a ) } a
> >***--***-
> >**---**--
> >---*--*--
> >*-***--**
> >**-*-****
>
> In this specific case is no need for special 'indexes' verb; i.
> will do just
> fine (with some magic):
>
> '#' ( b #&, i.$ a )"_ } a
> ----##--#
> #-##-##--
> ###--####
> #--#-#-#-
> -####---#
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