Tracy - symbols are a good way to go. Thanks for reminding me of them. Raul - that's what I was missing... I needed to use e. with the same shape: eg. arr e. (1 3 $ 'ab ')... Thank you. Your examples are nice and generic and faster than -:"1
( I have a 68 million row memory mapped table of 8 character strings I am searching ) arr =: 1e8 2 $ ('ab','cd') timespacex '''ab'' -:"1 arr' 0.543927 1.34219e8 timespacex 'arr e. ,:({:$arr){.''ab''' 0.398904 1.3435e8 ('ab' -:"1 arr) -: (arr e. ,:({:$arr){.'ab') Of course on my actual data it's slightly different: timespacex '''ZZZZ145'' -:"1 p' 0.109682 1.3422e8 timespacex '(p e. ,:({:$p){.''ZZZZ145'')' 0.728868 1.34222e8 $ p 68242450 8 ((p e. ,:({:$dat__p){.'ZZZZ145')) -: ('ZZZZ145' -:"1 p) 1 bill - Not sure what to do with E. Bjorn - 'ab' I. arr doesn't seem to help either... I was hoping for a mask of 0 1 0 1 for whether it was found or the indices On Thu, Aug 28, 2014 at 7:56 AM, Björn Helgason <gos...@gmail.com> wrote: > 'ab' I. arr > > __-------------------_ > https://groups.google.com/forum/m/#!forum/havaogskulamal > On 28 Aug 2014 10:58, "Joe Bogner" <joebog...@gmail.com> wrote: > >> Apologies for the extremely basic question, but I am struggling with >> this after searching NuVoc and the dictionary. >> >> How do I locate all the indices of 'ab' in arr? >> >> arr=:10 $ > ;: 'ab cd yyy' >> >> surely this isn't the best way: >> >> ] (3 = +/"1 'ab' i. arr) # arr >> ab >> ab >> ab >> ab >> >> >> I have been primarily dealing with boxed strings up to this point, >> which seemed easier since it was locating an atom in a list, not a >> list in a table (practicing my vocabulary here... I might be wrong >> though) >> >> >> Thanks, >> Joe >> ---------------------------------------------------------------------- >> For information about J forums see http://www.jsoftware.com/forums.htm >> > ---------------------------------------------------------------------- > For information about J forums see http://www.jsoftware.com/forums.htm ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm