On Sun, Nov 4, 2012 at 3:25 PM, Michal D. <michal.dobrog...@gmail.com> wrote: > (0 1 4). I follow the argument for (arcs=: $ #: I.@) but my J is slow. We > would have to be able to select an or of equals for example select from first > column where the value is 0 or 1 or 4.
Here's select the rows of Y where number in the first column is contained in X: X ((e.~ {."1) # ]) Y For example: sel0=: (e.~ {."1) # ] 7 21 35 sel0 i. 7 7 FYI, -- Raul ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm