Jon, I haven't been using J for a while so I tried your problem. In a way I must think like a beginner again. Here's my take after a false start where I used APL!
[A=:?6#50 40 5 19 46 34 40 >/A 1 >./A 46 i.$A 0 1 2 3 4 5 A=>./A 0 0 0 1 0 0 i.$A 0 1 2 3 4 5 (A=>./A) #i.$A 3 f=: 13 :'(y=>./y)#i.$y' f A 3 f (] = >./) # [: i. $ So this is "beginner Tacsit" that seems to work. Then it is fun to see what I can learn from the masters who have already solved your problem. Keep sending your questions. They are goo for all of us. Linda -----Original Message----- From: Programming [mailto:programming-boun...@forums.jsoftware.com] On Behalf Of 'Jon Hough' via Programming Sent: Tuesday, January 24, 2017 11:29 PM To: programm...@jsoftware.com Subject: Re: [Jprogramming] Return of max of list and it's index in single pass Yep, that's what I was looking for. Thanks! -------------------------------------------- On Wed, 1/25/17, Raul Miller <rauldmil...@gmail.com> wrote: Subject: Re: [Jprogramming] Return of max of list and it's index in single pass To: "Programming forum" <programm...@jsoftware.com> Date: Wednesday, January 25, 2017, 12:01 PM maxIndexAndValue=: ((i.,]) >./) I hope this helps, -- Raul On Tue, Jan 24, 2017 at 9:58 PM, 'Jon Hough' via Programming <programm...@jsoftware.com> wrote: > I want to get the max value of a list, and return the first index of its occurrence in the list, tacitly. > > My solution > > maxWithIndex =: {.@:I.@:(= >./), >./ > > works ok, but calculates >./ twice. Is there a tacit way to do this with only a single calc of >./ ? > > Thanks, > Jon > ---------------------------------------------------------------------- > 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