f=: {.^:(1=#)
f 'abc'
abc
$ f 'a'
$ f ,'a'
f^:proprosition y is equivalent to
if. proposition y do. f y else. y end.
----- Original Message -----
From: "Leigh J. Halliwell" <[EMAIL PROTECTED]>
Date: Saturday, April 7, 2007 10:14 am
Subject: [Jprogramming] Singleton Reduction
> Dear J Forum:
>
> Let X1 =. 'A' and X2 =. 1$'A'. Now X1 and X2 look equal, but
> because of
> different ranks X1 does not equal X2. I would like to reduce a
> singleton to
> an atom. If #X is 1, {.X does this. But I don't want to take the
> firstitem, if the string has more than one item. Can someone tell
> me a simple or
> efficient tacit expression that reduces one-rank, one-item arrays
> to atoms,
> and leaves other one-rank arrays unchanged? Can it be done
> without gerunds?
> Thanks.
>
> Sincerely,
>
> Leigh
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