Assuming you know the shape of the original argument:
x=: 5 6 ?@$ 100
x -: (;</.x) (;</.{i.&.>$x)} 5 6$0
1
Deriving the shape of the original x from </.x is left as an exercise for
the reader ...
On Wed, Feb 17, 2016 at 8:45 AM, Pascal Jasmin <[email protected]>
wrote:
> More specific to what I want, based on looking at diagonal relationships
> within data, I wish to update a value in the original matrix, but I think
> the original question is easier more flexible. I can't think of a better
> way than to generate indexes,
>
> (< 0 0) ,&< (1 0 ; 0 1) ....
>
>
>
>
> ----- Original Message -----
> From: Pascal Jasmin <[email protected]>
> To: Programming Forum <[email protected]>
> Sent: Wednesday, February 17, 2016 11:40 AM
> Subject: [Jprogramming] an inverse to oblique
>
> </. i.5 5
> +-+---+------+---------+------------+----------+--------+-----+--+
> |0|1 5|2 6 10|3 7 11 15|4 8 12 16 20|9 13 17 21|14 18 22|19 23|24|
> +-+---+------+---------+------------+----------+--------+-----+--+
>
> is there a way starting with the above boxes, to make the i. 5 5 table
> (without relying on magic within the data)
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