I'm adding one because it the list generated needs an extra item which isn't generated in the same way as the rest of them. The list has '1' prepended to it, but as '1' isn't prime, I don't need to bother having in the list so I thought it would be more efficient to add one to the tally when the percentage is calculated.
On 25 Sep 2011, at 21:46, Don Guinn wrote: > Apply the 1&p: to the list before doing the infixes. Cuts down the number of > times 1&p: is invoked. But why are you adding one to the number of items in > each infix? Seems like the 3 5 7 9 should give 0.75, not 0.6 . > > ((+/%#)&,)\_4,\1 p:3 5 7 9 13 17 21 25 31 37 43 49 > > On Sun, Sep 25, 2011 at 1:47 PM, David Vaughan <[email protected] >> wrote: > >> I've done: verb&,\ >> >> I arranged the list to be of shape 'x 4'. This seems to work. The problem >> I'm now having is that my verb is slow. Can this be refined (significantly)? >> >> +/@:(1&p:) % 1&+@:# >> >> It takes finds the percentage of items in the list which are prime. >> >> On 25 Sep 2011, at 20:04, Don Guinn wrote: >> >>> verb=.< >>> (verb&,)\_4,\3 5 7 9 13 17 21 25 31 37 43 49 >>> +-------+-------------------+-------------------------------+ >>> |3 5 7 9|3 5 7 9 13 17 21 25|3 5 7 9 13 17 21 25 31 37 43 49| >>> +-------+-------------------+-------------------------------+ >>> >>> >>> On Sun, Sep 25, 2011 at 12:44 PM, David Vaughan < >>> [email protected]> wrote: >>> >>>> I'm trying to apply a verb to infixes of length 4 but I want it to be >>>> cumulative. i.e. in the list: >>>> >>>> 3 5 7 9 13 17 21 25 31 37 43 49 >>>> >>>> I want: >>>> >>>> verb 3 5 7 9 >>>> verb 3 5 7 9 13 17 21 25 >>>> verb 3 5 7 9 13 17 21 25 31 37 43 49 >>>> >>>> Any help? Thanks. >>>> ---------------------------------------------------------------------- >>>> 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 >> > ---------------------------------------------------------------------- > For information about J forums see http://www.jsoftware.com/forums.htm ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
