Here's one idea of spiral order.
In it current for it has limitation that
number of items for g/ is 1+4*n
due to the way gerund is cyclically extended.
'`d c b a'=: ( ,~ )`( ,"0 1 )`( |[EMAIL PROTECTED],] )`( |[EMAIL
PROTECTED],"1 0~] )
g=. (d&.>)`(c&.>)`(b&.>)`(a&.>)
>g/ 3}. |.(i.@>:@{: (e.<;.2[) ]) <:+/\2#1+i.6
16 15 14 13 12
17 4 3 2 11
18 5 0 1 10
19 6 7 8 9
20 21 22 23 24
--- Roger Hui <[EMAIL PROTECTED]> wrote:
> Now that we have mastered zigzag order, how about the
> spiral order? For example, the spiral order for a
> 4 5 array is:
>
> 0 1 2 3 4
> 13 14 15 16 5
> 12 19 18 17 6
> 11 10 9 8 7
>
>
> ----------------------------------------------------------------------
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>
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