Hello Henry, thanks a lot! I must have read this page once, but hadn't made the connection. Adding !.0 does the trick wonderfully, and I can forget my workaround (what workaround?)
Ben On Wed, 30 Aug 2023 at 12:19, Henry Rich <henryhr...@gmail.com> wrote: > See https://code.jsoftware.com/wiki/Vocabulary/IFamily#Performance . > > Tolerant i.-family operations on arrays are tough. They end up doing > sequential search. ~.!.0 will be much faster, if you don't need the > tolerance. > > Henry Rich > > On 8/29/2023 8:47 PM, Ben Gorte wrote: > > Dear J, > > > > I noticed that ~. (nub) can become very slow on float arrays - is that > > known? > > Mine was a 9 million times 6 array and it seemed to hang on my laptop. > > This can be demonstrated as: > > > > idx =: 4$.$.10 10 10 10 10 10$1 NB. a million different tuples of 6 > integers > > > > 6!:2 'echo $ ~. idx' > > > > 1000000 6 > > > > 0.068726 > > > > fdx =. 0.0+idx NB. now with floats: > > > > 6!:2 'echo $ ~. fdx' > > > > 1000000 6 > > > > 225.568 > > > > JVERSION > > > > Engine: j9.4.1/j64/linux > > > > Build: commercial/2023-02-27T15:21:43/clang-11-0-0/SLEEF=1 > > > > Library: 9.4.21 > > > > Qt IDE: 2.0.3/5.12.8(5.15.3) > > > > Platform: Linux 64 > > > > Installer: j9.4 install > > > > InstallPath: /home/ben/j9.4 > > > > Contact: www.jsoftware.com > > > > I haven't tried other J versions, except the (current) playground in > > Firefox. There it is similar. > > > > > > Other than that I am continuing to enjoy J, daily. > > > > > > Greetings, > > > > Ben > > ---------------------------------------------------------------------- > > 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
