u/\.&|.s is probably more efficient.

   s=:i.1000 2

   ts'plus/@:|.\ s'
0.42737873 38976

   ts'plus/\.&.|. s'
0.00062138806 18496


R.E. Boss

> -----Oorspronkelijk bericht-----
> Van: [email protected] [mailto:programming-
> [email protected]] Namens Graham Parkhouse
> Verzonden: woensdag 3 maart 2010 11:39
> Aan: [email protected]
> Onderwerp: [Jprogramming] Efficiency of u/@:|.\
> 
> I have a matrix S of n vectors, s0, s1, s2 etc and a verb u with which I
> can
> build a matrix T of n vectors, t0, t1, t2 etc by the following procedure:
> 
> t0=: s0
> t1=: s1 u t0
> t2=: s2 u t1 etc
> 
> T=: u/@:|.\S    will do it, but will the interpreter recognize the quick
> way
> of doing u/@:|.\ (for any verb u)?
> 
> The problem I have described is very common in engineering. I've always
> used
> a loop before and am now aiming for something tidier. But will it be
> efficient?
> 
> Regards
> 
> Graham
> 
> 
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