+/@:((*+/\)"1)@= 1 2 1 1 2 1 1 2 3 2 is the correct answer for the running count. (Ask your (grand)child.)
Elegant, but probably not efficient. R.E. Boss > -----Original Message----- > From: Programming <[email protected]> On > Behalf Of Louis de Forcrand > Sent: vrijdag 30 maart 2018 13:55 > To: [email protected] > Subject: Re: [Jprogramming] running count > > Hiya, > > rc=: i.~ (] - {) /:@/: > rc 1 2 1 1 2 > 0 0 1 2 1 > > Cheers, > Louis > > > On 28 Mar 2018, at 20:32, Joe Bogner <[email protected]> wrote: > > > > I think this is an easy one but it's escaping me. How to calculate a > > running count of an item in a list? > > > > runct (1,2,1,1,2) -: 0,0,1,2,1 > > runct (5,6,5,5,6) -: 0,0,1,2,1 > > > > This seems to be a good start > > > > = (5,6,5,5,6) > > 1 0 1 1 0 > > 0 1 0 0 1 > > ---------------------------------------------------------------------- > > 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
