Missing was plus=:+
(plus/@:|.\ s)-:plus/\.&.|. s 1 R.E. Boss > -----Oorspronkelijk bericht----- > Van: [email protected] [mailto:programming- > [email protected]] Namens R.E. Boss > Verzonden: woensdag 3 maart 2010 13:26 > Aan: 'Programming forum' > Onderwerp: Re: [Jprogramming] Efficiency of u/@:|.\ > > 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 > > > > > > ---------------------------------------------------------------------- > > For information about J forums see http://www.jsoftware.com/forums.htm > > ---------------------------------------------------------------------- > For information about J forums see http://www.jsoftware.com/forums.htm ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
