Here's what I'd start with: chidot=: #@[ ({. i. }.) ,
If that was too slow, I'd probably build an explicit work-alike, with intermediate variables for shapes. (>;:'SF SY PK ...') chidot (>;:'SF SY') 0 1 -- Raul On Wed, Apr 11, 2018 at 4:35 PM, Joe Bogner <joebog...@gmail.com> wrote: > I often get tripped up with different trailing shapes when using i. with > char arrays. I must not be the only one[1] > > Does this look like a suitable utility to deal with it or is there a more > common way? > > Y1=:0&{:: > Y2=:1&{:: > idotfill =. (( ( (_,]) {. Y1@[) i. ((_,]) {. Y2@[) ) {:@$@Y2 >. {:@$@Y1) f. > > idotfill (>'SF';'SY';'PK ');(>'SF';'SY') > 0 1 > > compare with > > NB. different trailing shape > (>'SF';'SY';'PK ') i. (>'SF';'SY') > 3 3 > > NB. remove the trailing space on PK > > (>'SF';'SY';'PK') i. (>'SF';'SY') > 0 1 > > > [1] - "y must match the entire row of x (including any trailing fill > letters) for (i.) to find it. Otherwise (i.) returns (#x) (signifying "not > found"), concealing your error." > > http://code.jsoftware.com/wiki/Vocabulary/idot#dyadic > ---------------------------------------------------------------------- > For information about J forums see http://www.jsoftware.com/forums.htm ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm