While &> *does* have the effect of unboxing, it's use in generic "every" suggests to me that it's primary use here is just to set the ranks of the preceding verb to 0 0 0, which are the ranks of unbox. I suppose unbox was chosen not only because it's ranks are 0 0 0 but also because it works on both boxed AND unboxed data, so making it suitable for the common adverb "every".
The fact that "every" takes 9x more time and 2x more space than "0 makes me wonder if a different (more efficient?) verb with ranks 0 0 0 could be used in the "every" adverb?) I can't find any reference to the "every" adverb in any of the documentation) > From: [EMAIL PROTECTED] > To: [email protected] > Subject: RE: [Jprogramming] "every" adverb > Date: Thu, 12 Jun 2008 10:24:54 -0400 > > The purpose of &> is to unbox atoms of the operands. If you don't > need to do that, "0 is better. > > In contrast, u&.> was better than <@u"0 even for unboxed > operands, last I looked. > > Henry Rich > > > -----Original Message----- > > From: [EMAIL PROTECTED] > > [mailto:[EMAIL PROTECTED] On Behalf Of > > Richard Donovan > > Sent: Thursday, June 12, 2008 9:53 AM > > To: Programming forum > > Subject: [Jprogramming] "every" adverb > > > > > > I have been playing around with the adverb "every" supplied > > with the system: > > > > d=:i.10 > > < d > > --------------------┐ > > │0 1 2 3 4 5 6 7 8 9│ > > L-------------------- > > every > > &> > > < &> d > > --T-T-T-T-T-T-T-T-T-┐ > > │0│1│2│3│4│5│6│7│8│9│ > > L-+-+-+-+-+-+-+-+-+-- > > < "0 d > > --T-T-T-T-T-T-T-T-T-┐ > > │0│1│2│3│4│5│6│7│8│9│ > > L-+-+-+-+-+-+-+-+-+-- > > d=:i.1e5 > > (< &> d) -: (< "0 d) > > 1 > > ts > > 6!:2 , 7!:[EMAIL PROTECTED] > > > > 10 ts '< &> d' > > 0.426803 1.50782e7 > > 10 ts '< "0 d' > > 0.0517512 7.33485e6 > > > > > > It seems that "every" forces the preceding verb to take on > > the ranks of verb> (open) > > i.e. 0 0 0 > > > > As you can see from the ts tests I ran, it seems that "every > > &>" makes a serious time > > difference to the expression, and also uses more space. > > > > If the only purpose of &> is to force the verb ranks to be 0 > > 0 0 why not just use the > > expression v "0 which is not only more obvious as to what > > it's doing but also seems > > much quicker and leaner? > > _________________________________________________________________ > > Great deals on almost anything at eBay.co.uk. Search, bid, > > find and win on eBay today! > > http://clk.atdmt.com/UKM/go/msnnkmgl0010000004ukm/direct/01/-- > > -------------------------------------------------------------------- > > For information about J forums see > > http://www.jsoftware.com/forums.htm > > ---------------------------------------------------------------------- > For information about J forums see http://www.jsoftware.com/forums.htm _________________________________________________________________ Great deals on almost anything at eBay.co.uk. Search, bid, find and win on eBay today! http://clk.atdmt.com/UKM/go/msnnkmgl0010000004ukm/direct/01/---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
