e. is more concise than +./@:= Is there some advantage (outside of educational value) to using +./@:=?
Thanks, -- Raul On Tue, Nov 10, 2020 at 10:01 PM Henry Rich <[email protected]> wrote: > > Agreed. But you should NEVER use +./ x = y . Use x +./@:= y which > stops at the first match. > > Henry Rich > > On 11/10/2020 9:58 PM, bill lam wrote: > > atom e. vector is common and IMO more intuitive than +./ atom = vector > > > > > > On Wed, Nov 11, 2020 at 10:35 AM Henry Rich <[email protected]> wrote: > > > >> (vector e. atom) and (atom e. vector) does a loop through each pair of > >> atoms and creates the result one value at a time. > >> > >> (vector = atom) does 32-byte parallel compares and is much faster. > >> > >> Henry Rich > >> > >> On 11/10/2020 7:27 PM, bill lam wrote: > >>> please correct me if i am wrong, > >>> scalar e. vector > >>> has already optimized for avx2 and short-circuited once 1 found. > >>> > >>> However > >>> vector e. scalar vs vector = scalar > >>> is a matter of personal preference, computational efficiency shouldn't > >> be a > >>> problem. > >>> > >>> > >>> On Wed, Nov 11, 2020, 7:44 AM Henry Rich <[email protected]> wrote: > >>> > >>>> Testing for special cases isn't free, and this case seems rare. But the > >>>> = code processes 32 bytes at a time, while the e. does just one. Might > >>>> be worth doing in the engine; certainly you should do it in your code. > >>>> > >>>> Henry Rich > >>>> > >>>> On 11/10/2020 5:21 PM, Joseph Novakovich wrote: > >>>>> Should this instead be considered a performance bug in 'e.'? > >>>>> > >>>>> On 11/10/20, Joseph Novakovich <[email protected]> wrote: > >>>>>> The change is replacing the lines > >>>>>> > >>>>>> b=. dat e. LF NB. or fd in chopstring > >>>>>> c=. dat e. sd > >>>>>> > >>>>>> with > >>>>>> > >>>>>> b=. dat = LF > >>>>>> c=. dat = {.sd > >>>>>> > >>>>>> in 'chopstring' and 'fixdsv' > >>>>>> > >>>>>> Joseph > >>>>>> > >>>>>> > >>>>>> > >>>>>> On 11/10/20, Henry Rich <[email protected]> wrote: > >>>>>>> I would offer an opinion, except I can't figure out what the change > >> is. > >>>>>>> Henry Rich > >>>>>>> > >>>>>>> On 11/10/2020 1:25 PM, Joseph Novakovich wrote: > >>>>>>>> Hello, > >>>>>>>> > >>>>>>>> I noticed a spot for performance improvement in 'fixdsv' and > >>>>>>>> 'chopstring'. I opened two pull requests on github for the base9 > >>>>>>>> library and the tables/dsv addon: > >>>>>>>> > >>>>>>>> https://github.com/jsoftware/tables_dsv/pull/1 > >>>>>>>> https://github.com/jsoftware/base9/pull/1 > >>>>>>>> > >>>>>>>> Basically, bitmasks were using 'e.' to find occurrences of a single > >>>>>>>> char in the input. Using '=' instead seems to give around 10-20% > >>>>>>>> speedup. > >>>>>>>> > >>>>>>>> Joseph > >>>>>>>> > >> ---------------------------------------------------------------------- > >>>>>>>> For information about J forums see > >>>> http://www.jsoftware.com/forums.htm > >>>>>>> -- > >>>>>>> This email has been checked for viruses by AVG. > >>>>>>> https://www.avg.com > >>>>>>> > >>>>>>> > >> ---------------------------------------------------------------------- > >>>>>>> For information about J forums see > >> http://www.jsoftware.com/forums.htm > >>>>> ---------------------------------------------------------------------- > >>>>> For information about J forums see http://www.jsoftware.com/forums.htm > >>>> -- > >>>> This email has been checked for viruses by AVG. > >>>> https://www.avg.com > >>>> > >>>> ---------------------------------------------------------------------- > >>>> For information about J forums see http://www.jsoftware.com/forums.htm > >>>> > >>> ---------------------------------------------------------------------- > >>> For information about J forums see http://www.jsoftware.com/forums.htm > >> > >> -- > >> This email has been checked for viruses by AVG. > >> https://www.avg.com > >> > >> ---------------------------------------------------------------------- > >> For information about J forums see http://www.jsoftware.com/forums.htm > >> > > ---------------------------------------------------------------------- > > For information about J forums see http://www.jsoftware.com/forums.htm > > > -- > This email has been checked for viruses by AVG. > https://www.avg.com > > ---------------------------------------------------------------------- > For information about J forums see http://www.jsoftware.com/forums.htm ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
