Alternatively, g (] #~ [: */ e."1~) ~.,g 3 5
On Tue, Oct 23, 2018 at 7:40 AM Roger Hui <[email protected]> wrote: > > ix&.>/ <"_1 g where ix is Mike's intersection verb. > > > On Tue, Oct 23, 2018 at 7:33 AM Skip Cave <[email protected]> wrote: > >> Thanks Rob, Bo, & Mike for your enlightening answers. >> >> So now I have a similar question on a simpler data set: >> >> Given: >> >> g=.4 5$ 1 2 3 4 5 2 3 4 5 6 5 3 7 1 8 3 8 6 1 5 >> >> g >> >> 1 2 3 4 5 >> >> 2 3 4 5 6 >> >> 5 3 7 1 8 >> >> 3 8 6 1 5 >> >> >> How do I find the common integers in g across all rows (the answer is 3 >> 5)? >> >> >> Rob's scheme works if I box g: >> >> >> in each/ ~. each {g >> >> ┌───┐ >> >> │3 5│ >> >> └───┘ >> >> Or even simpler: >> >> in each/ {g >> >> ┌───┐ >> >> │3 5│ >> >> └───┘ >> >> I'm not sure how to apply Bo's +./ scheme to g: >> >> +./g >> >> 1 1 1 1 1 >> >> Same for Mike's ix verb: >> >> ix =: ([ -. -.) >> >> ix g >> >> 1 2 3 4 5 >> >> 2 3 4 5 6 >> >> 5 3 7 1 8 >> >> 3 8 6 1 5 >> >> >> Skip >> >> On Tue, Oct 23, 2018 at 1:31 AM Skip Cave <[email protected]> >> wrote: >> >> > Given the integers: 1998 2997 3996 4995 5994 6993 7992 8991 >> > Find the common prime factors in all of these integers. >> > >> > Obviously we can find the prime factors of each of the integers: >> > >> > q: 1998 2997 3996 4995 5994 6993 7992 8991 >> > >> > 2 3 3 3 37 0 0 >> > >> > 3 3 3 3 37 0 0 >> > >> > 2 2 3 3 3 37 0 >> > >> > 3 3 3 5 37 0 0 >> > >> > 2 3 3 3 3 37 0 >> > >> > 3 3 3 7 37 0 0 >> > >> > 2 2 2 3 3 3 37 >> > >> > 3 3 3 3 3 37 0 >> > >> > >> > What J expression will find the common factors in all 6 of these >> integers? >> > >> > (the result of the expression should be that there are two common >> factors >> > - 3 & 37) >> > >> > Skip >> > >> > >> ---------------------------------------------------------------------- >> For information about J forums see http://www.jsoftware.com/forums.htm > > ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
