cd=: (|. +/ ])@[EMAIL PROTECTED] (</.&, /: {./.&,[EMAIL PROTECTED]) ]
cd=: </.&.(|."1"_)
I should have called them diagonals instead of
counter diagonals. It's </.y that gets the
counter diagonals (aka oblique lines).
----- Original Message -----
From: Roger Hui <[EMAIL PROTECTED]>
Date: Thursday, January 4, 2007 11:42 am
Subject: Re: [Jgeneral] Array-oriented proof?
...
> 4. cd G computes the list of counter-diagonals of a
> square matrix, where
>
> cd=: (|. +/ ])@[EMAIL PROTECTED] (</.&, /: {./.&,[EMAIL PROTECTED]) ]
>
> For example,
> i. 5 5
> 0 1 2 3 4
> 5 6 7 8 9
> 10 11 12 13 14
> 15 16 17 18 19
> 20 21 22 23 24
> cd i.5 5
> +--+-----+--------+----------+------------+---------+------+---+-+
> |20|15 21|10 16 22|5 11 17 23|0 6 12 18 24|1 7 13 19|2 8 14|3 9|4|
> +--+-----+--------+----------+------------+---------+------+---+-+
...
----------------------------------------------------------------------
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