I noticed, coming back from a short vacation, that I did not paste the final
version of involute2; here it is:
lr'involute2'
([ $ /:@(+/\@(,@(] {. |:@((1 0 + [EMAIL PROTECTED]@|.)@[)) # +:@] $ (, -)@(1 ,
{:@[))))
<./
The relative performance is not affected:
st'involute0 400 600'
6302784 0.0354399791
st'involute1 400 600'
4195328 0.0379573382
st'involute2 400 600'
3155008 0.034524779
> [EMAIL PROTECTED] On Behalf Of Jose Mario Quintana
> lr'lr'
> 5!:5@<
>
>
> Eesuk's explicit generalization of a classic solution:
>
> lr'involute0'
> 3 : 0
> t=.<./'M N'=.y
> p=.,t{.|:(>:i.-N),:i.-M
> d=.(+:t)$(,-)1,N
> y$/:+/\p#d
> )
>
> Eesuk's tacit version:
>
> lr'involute1'
> $ /:@(+/\)@(,@(<./ {. |:@(1 0 + [EMAIL PROTECTED]@|.)) # +:@<./ $ (, -)@(1 ,
> {:))
>
> A slight variation:
>
> lr'involute2'
> ([ $ /:@(+/\@(,@(] {. |:@((1 0 + [EMAIL PROTECTED]@|.)@[)) # +:@] $ (, -)@(1
> , {:@[))))
> {.
>
> lr'st'
> 7!:2 , 6!:2
>
> st'involute0 400 600'
> 6302784 0.025494581
> st'involute1 400 600'
> 4195328 0.0252504159
> st'involute2 400 600'
> 3155008 0.0255353683
>
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