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
> >>>>>>
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