On Thu, Feb 4, 2010 at 5:07 PM, Dan Bron <[email protected]> wrote:
> ] BOARD0 =: 5 5 $ 0 0 0 0 0 0 0 0 0 0 1 0 1 0 1 0 0 0 0 0 0
> 0 0 0 0
...
PUSH =: 3 2
>
> can you write a dyad out such that:
>
> ] BOARD1 =: BOARD0 out PUSH
> 0 0 0 0 0
> 0 0 0 0 0
> 1 0 0 0 1
> 0 1 1 1 0
> 0 0 1 0 0
>
>
> in an elegant, array-oriented way?
out=: [ ~: 1 1}. _1 _1}. -...@] |.!.0 (0 1 0,1,:0 1 0) {.~ 2 + $...@[
If PUSH were represented using negative numbers,
-...@] could be replaced with ]
Alternatively, if we can assume a 5x5 board,
out5x5=: [ ~: 1 1}. _1 _1}. (7 7{.0 1 0,1,:0 1 0) |.!.0~ -...@]
(With the same comment about the possible alternative
representation for PUSH. But this one could also be
implemented as a hook by dropping the [ on the left.)
--
Raul
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