Zsbán Ambrus wrote:
>
> Dear Jsoftware,
>
> Is there any chance that a future J version would optimize the monad
> u/\. for any verb u to make only linear number of calls to u instead
> of quadratic?
>
> I know this would break the case when u has side effects, but I still
> believe this would be a useful feature (if documented), for it would
> help in lots of cases but break only little code.
>
> As a model, for any verb u and noun y, (u/\. y) could be executed as
> if it was (>,(];~>@[u>@{...@])/<"_1 y).
>
> Ambrus
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> For information about J forums see http://www.jsoftware.com/forums.htm
>
>
Linear number of calls can be also checked out like this:
v =: dyad : 0
n=:n+1
x + y
)
n=:0
v/\.i.10
45 45 44 42 39 35 30 24 17 9
n
9
+/\.i.10
45 45 44 42 39 35 30 24 17 9
DoJ says: "u\.y has #y items resulting from applying u
to suffixes of y ,[...]". If we stick to this definition, what should
be the value of n in the above example?
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