That's reinforcing my point--there are no more than three significant axes there.
a=. 2 3 4 5 6 7 8 9 10 +/ .(*"4)&i. 7 8 9 10 b=. ((*/2 3 4 5),6,(*/7 8 9 10)) +/ .(*"1)&i. */7 8 9 10 a -:&, b 1 On Mon, 30 May 2022, Raul Miller wrote: > On Mon, May 30, 2022 at 1:31 AM Elijah Stone <elro...@elronnd.net> wrote: >> Rank is about projecting a 2- or 3-dimensional structure onto >> multidimensional arrays. > > Those are common cases, but the concepts behind the notation do > support operations like: > > $2 3 4 5 6 7 8 9 10 +/ .(*"4)&i. 7 8 9 10 > 2 3 4 5 7 8 9 10 > > And, +/ there could be replaced with something rather different... > > That said, data sets with high dimensionality tend to run into machine > limitations (some of which I believe sparse arrays were meant to > address). > > Thanks, > > -- > Raul > ---------------------------------------------------------------------- > For information about J forums see http://www.jsoftware.com/forums.htm ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
