http://www.jsoftware.com/books/help/dictionary/d530n.htm
If m is not a gerund, x m} y is formed by
replacing by x those parts of y selected
by m&{ .
To get "those parts of y selected by m&{", the
interpreter applies m&{ to i.$y . Thus:
m=: (<1;2 3),<0;7
y=: 2 9$'-'
m&{ i.$y
11 12
7 0
The last result are the indices of the atoms of
those parts of y selected by m&{ .
If you don't care for i.$y , use whatever set of
canonical indices you do care for, and you still
get "non-intuitive" behaviour.
----- Original Message -----
From: Andrew Nikitin <[EMAIL PROTECTED]>
Date: Wednesday, July 19, 2006 8:09 am
Subject: [Jprogramming] }
> >The interpreter is working as specified. The result is not
> "intuitive"
> >because in this case
> >atoms of the index array do not select subarrays that are the same
> >shape. -- RogerHui 2006-07-18 23:06:08
>
> Where exactly this is specified? Dictionary page for } does not
> mention
> shape of subarrays.
>
> >Could somebody please explain me where asterisk in top left
> corner is
> >coming
> >from?
> > '*' ((<1;2 3),<0;7) } 2 9$'-'
> >*------*-
> >--**-----
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