I recently sent the following email to Henry. I thought it would be nice to know different ways of getting cartesian product(except the built-in catalogue) that other people know.
So, do you know of different ways of getting the cartesian product such as, cpd=:,"_1 _"_ _1 cp=:[: > [: ([: ,/ cpd)&.>/ ,&.> /:~ cp 1 2;3 4 5;0;8 9 1 3 0 8 1 3 0 9 1 4 0 8 1 4 0 9 1 5 0 8 1 5 0 9 2 3 0 8 2 3 0 9 2 4 0 8 2 4 0 9 2 5 0 8 2 5 0 9 2008/1/29, June Kim <[EMAIL PROTECTED]>: > Hello, > > on file:///C:/j601/system/extras/help/jforc/odds_and_ends.htm#_Toc141158196 > > There is a definition for cartesian product but I think there is a typo. > > <quote> > The cartesian product can be written in J as ,"_1 " _1 (or, if the > items have rank 0, by the table adverb ,"0/), as seen in this example > where we box each result: > > 'io' <@,"_1 " _1 'nfd' > </quote> > > I think it should've been instead: > > ,"_1 _"_ _1 NB. to be precise and revealing the intention, but... > ,"_1 "_ _1 NB. this would work, too Actually, the latter works in the given example, but not in general cases. > > > Thank you for your work. > > June Kim > ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
