I am using fftw
Thanks,
--
Raul
On Wed, Mar 2, 2022 at 7:40 PM Henry Rich <henryhr...@gmail.com> wrote:
>
> If you are measuring performance, use fftw.
>
> FFT will be better on big problems.
>
> Henry Rich
>
> On Wed, Mar 2, 2022, 7:35 PM Raul Miller <rauldmil...@gmail.com> wrote:
>
> > Yes, ... maybe I should replace my caching wrapper with M.
> >
> > That said, using the fft cyclotomic000 implementation and the caching
> > wrapper from the rosettacode page (and the fftw implementation for fft
> > and ifft):
> >
> > taskorder=: {{
> > r=.$k=.0
> > while.y>#r do.k=.k+1
> > if.(1+#r) e.|u k do.
> > r=. r,k
> > k=. k-1
> > end.
> > end.r
> > }}
> >
> > timespacex 'cyclotomic taskorder 10 [ cache=: 2 {. cache'
> > 8.17343 5.70164e8
> >
> > vs.
> >
> > timespacex '(cyclotomic=:{{if.2>y do._1 1 else. unpad cyclotomic000
> > y end.}}M."0) taskorder 10'
> > 15.1576 6.86114e8
> >
> > I'm not sure that this is an improvement.
> >
> > --
> > Raul
> >
> > On Wed, Mar 2, 2022 at 7:01 PM 'Michael Day' via Programming
> > <programm...@jsoftware.com> wrote:
> > >
> > > Interesting! I've got some thoughts on this, but it's getting late
> > > here, so I'll
> > > defer a fuller reply.
> > >
> > > Meanwhile, a quickie: since the memoisation does seem to work, might
> > > it be better
> > > to dispense with cache? A pity as you put some effort into its use,
> > > but the code is
> > > simpler without it.
> > >
> > > Thanks,
> > >
> > > Mike
> > >
> > > On 02/03/2022 19:57, Raul Miller wrote:
> > > > I've updated the rosettacode page to include this implementation. And,
> > > > I plan on updating the j wiki polynomial division essay, also, once I
> > > > think through a bit how to describe this approach. (Descriptive
> > > > phrases and sentences would be welcome. Documentation needs good
> > > > perspectives, above all else.)
> > > >
> > > > For the purpose of the rosettacode page, I used a different phrasing
> > of rou:
> > > >
> > > > rou =: {{(,j.) r,(%:0j1),j.+|.}.r=.^o.j.(i.@%&8 % -:) y}} NB.
> > > > roots of unity
> > > >
> > > > This seems (to me) to be more concise, and straightforward, than the
> > > > purely tacit expression.
> > > >
> > > > (That said, I'm not sure if this change in notation would be a good
> > > > fit for the FFT essay.)
> > > >
> > > > Thanks,
> > > >
> > >
> > >
> > > --
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> > >
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