This is getting interesting; I was already impressed with Js speed being only twice as slow as the C version, and faster than the R version of the same code.
Looking forward to that 806 beta 3! Btw I should uninstall the latest (stable) and start afresh? Sent from my iPhone > On Apr 17, 2017, at 5:03 PM, Raul Miller <[email protected]> wrote: > > I think you were surprised by > http://www.jsoftware.com/help/dictionary/special.htm > > Specifically the special handling for +/ .* (which is handled at > parsing time rather than at execution time - the way you have things > arranged, the parser will not see +/ .* and hypothetically you could > arrange for sum .* in contexts where sum was defined differently). > > I hope this helps, > > -- > Raul > > > On Mon, Apr 17, 2017 at 4:51 PM, Michael Goodrich > <[email protected]> wrote: >> Greetings: >> >> Got a nasty surprise today. have a non-trivial J app with the following >> supporting original definitions: >> >> sum =. +/ >> dot =. +/ . * >> sqrd =. *: >> ssq =. +/ @: sqrd >> >> >> Which I changed (thinking I was being elegant) to >> >> sum =. +/ >> dot =. sum . * >> sqrd =. *: >> ssq =. sum @: sqrd >> >> After this change the run time increased by a factor of 5! >> >> Insights? >> ---------------------------------------------------------------------- >> 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
