Basically, you put the definition of f in parenthesis (though it
already is, so no actual change needed there), and the definition of g
in parenthesis.
You can even get the interpreter to do this for you:
9!:3]5
make_move
g f
make_move f.
((+. *. -.@:*.) +./) (1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 |.!.0~ 3 1 $ -)
Though, I would be tempted to replace 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0
with (15{.1) in a definition.
I hope this helps,
--
Raul
On Sat, May 27, 2017 at 10:28 PM, Michael Rice <[email protected]> wrote:
> NB. 15 position peg solitaire
> NB. The board (position 5 initially vacant)
>
> NB. 0
> NB. 1 2
> NB. 3 4 5
> NB. 6 7 8 9
> NB. 10 11 12 13 14
>
> xor =: ((+.)*.(-.@:*.))
> board =: 1 1 1 1 1 0 1 1 1 1 1 1 1 1 1 NB. 0s for vacant, 1s occupied
> board
> 1 1 1 1 1 0 1 1 1 1 1 1 1 1 1
> move =: 0 2 5
> move
> 0 2 5
> board xor +./((1 0 0 0 0 0 0 0 0 0 0 0 0 0 0) |.!.0~ 3 1 $ -) move
> 0 1 0 1 1 1 1 1 1 1 1 1 1 1 1 NB. The desired result, a new board
> f =: ((1 0 0 0 0 0 0 0 0 0 0 0 0 0 0) |.!.0~ 3 1 $ -)
> f move
> 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0
> 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0
> 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0
> +./f move
> 1 0 1 0 0 1 0 0 0 0 0 0 0 0 0 NB. Move 0 2 5 expressed as 15 element
> binary array
> board xor +./f move
> 0 1 0 1 1 1 1 1 1 1 1 1 1 1 1 NB. Again, the desired result
> board NB. Both board and move unchanged
> 1 1 1 1 1 0 1 1 1 1 1 1 1 1 1
> move
> 0 2 5
> g =: xor +./
> make_move =: g f
> board make_move move
> 0 1 0 1 1 1 1 1 1 1 1 1 1 1 1 NB. Again, the desired result
>
> ++++++++++++++++++++++++++++++++++
>
> The question: How to write make_move without creating subfunctions f and g?
>
> I've tried several definition variations and keep getting 'length error'
> messages upon usage.
>
> One example:
> make_move =: xor+./((1 0 0 0 0 0 0 0 0 0 0 0 0 0 0) |.!.0~ 3 1 $ -)
> board make_move move
> |length error: make_move
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