What e does in the while loop is matching the items of x with those of y.
For this we have the rank conjunction, which in this case is "0 1 .
Only ravel the result.
e1=: 4 : 0"0 1
w=. i. 0
z=. x(|{.)y
select. z
case. 0 do. w=. w,+/y
case. 1 do. w=. w,*/y
case. 2 do. w=. w,>./y
case. do. w=. w
end.
w
)
(5 ?...@$ 4) ,@:e1 5 4 ?...@$ 20
52 19 38 0 30
R.E Boss
> -----Oorspronkelijk bericht-----
> Van: [email protected] [mailto:programming-
> [email protected]] Namens Brian Schott
> Verzonden: dinsdag 2 februari 2010 4:42
> Aan: [email protected]
> Onderwerp: [Jprogramming] loopless programming question
>
>
> I am working on revising an Einstein puzzle solving
> program which currently is written as long while. loops, so
> that the looping is minimized in the revision. I think the
> answer to my question has been discussed in these forums as
> a way to more efficiently calculate a result when the number
> of different calculations is small relative to the length of
> the list of data that is being operated upon. But I cannot
> imagine how to search for that thread, so I have tried to
> create a verb that shows the while. loop process in my
> current program but does not resemble the real problem which
> is more complex. I hope that with help on revising this
> simplified problem to eliminate the while. loop, I can
> master my real one.
>
> Thank you,
>
> e =: dyad define"1 2
> assert. x -:&{.&$ y
> w=. i. 0
> while. #y do.
> b=. {. y
> z=. x|&{.b
> select. z
> case. 0 do. w=. w,+/b
> case. 1 do. w=. w,*/b
> case. 2 do. w=. w,>./b
> case. do. w=. w
> end.
> x=.}.x
> y=.}.y
> end.
> w
> )
>
> NB. more realistically the 5's below would be 300's.
> NB. but this example is adequate, I hope
> (5 ?...@$ 4) e 5 4 ?...@$ 20
> 52 19 38 30
> (5 ?...@$ 4) ; 5 4 ?...@$ 20
> +---------+-----------+
> |2 3 3 0 2| 6 15 19 12|
> | |14 19 0 17|
> | | 0 14 6 18|
> | |13 18 11 12|
> | |18 0 10 2|
> +---------+-----------+
> 2 3 3 0 2|6 14 0 13 18
> 0 2 0 13 0
>
> --
>
> (B=) <----------my "sig"
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