He told me.
Which of course, means I may have mis-reported some subtleties and/or
details.
--
Raul
On Sat, Nov 3, 2012 at 12:22 PM, Roger Hui <rogerhui.can...@gmail.com>wrote:
> > It's probably worth keeping in mind that originally, Iverson did not
> > want any length errors on arrays, but because length errors catch so
> > many problems they have been incorporated in the language.
>
> How do you know this? If there is a citation to a paper backing this up
> that'd be good.
>
>
>
>
>
> On Sat, Nov 3, 2012 at 7:30 AM, Raul Miller <rauldmil...@gmail.com> wrote:
>
> > Brian Schott already answered your question?
> >
> > Remember we are working with polynomials. So, from a results
> > perspective, these are equivalent:
> >
> > 1 2 1 p. y
> > 1 2 1 0 0 p. y
> > 1 2 1 0 0 0 0 p. y
> >
> > You will probably notice a relationship between these zeros and the
> > leading zeros in decimal numbers and the leading ones in array shape?
> >
> > It's probably worth keeping in mind that originally, Iverson did not
> > want any length errors on arrays, but because length errors catch so
> > many problems they have been incorporated in the language.
> >
> > In contexts where length errors are not appropriate, we have a variety
> > of mechanisms available to us:
> >
> > We can find the length of both arrays and use take ({.) with their
> > maximum (best in explicit contexts) -- x dyad&((x>.y)&{.)
> >
> > We can join the arrays using ,: and then reduce them (dyad/)@,:
> >
> > We can use sparse arrays with an arbitrarily large array index x
> > dyad&(9e9{.$.) y -- note that _ does not work here, as a length, note
> > also that if we take this approach we will need to extract the array
> > size somehow, later, if we ever want a dense array, and finally note
> > that this use of "array shape" starts feeling more like the concept of
> > "type" popular in some other languages (as opposed to "dependent type"
> > -- here, it's just something arbitrary which distinguishes between
> > otherwise identically appearing structures). We have some other
> > issues with sparse arrays, also...
> >
> > And, of course, we can often find algorithmically relevant ways of
> > handing array length. These tend to be related to the purpose of our
> > algorithms.
> >
> > I hope this helps,
> >
> > --
> > Raul
> >
> > On Fri, Nov 2, 2012 at 5:36 PM, Linda Alvord <lindaalv...@verizon.net>
> > wrote:
> > > I answered the wrong message. What about the final two zero's in the
> > > result?
> > >
> > > Linda
> > >
> > >
> > > -----Original Message-----
> > > From: programming-boun...@forums.jsoftware.com
> > > [mailto:programming-boun...@forums.jsoftware.com] On Behalf Of Raul
> > Miller
> > > Sent: Friday, November 02, 2012 10:46 AM
> > > To: programm...@jsoftware.com
> > > Subject: Re: [Jprogramming] Taylor series
> > >
> > > On Fri, Nov 2, 2012 at 5:18 AM, Linda Alvord <lindaalv...@verizon.net>
> > > wrote:
> > >> Raul, I haven't gotten to t. yet, but I did manage not to use (f*g)
> or
> > > p.
> > >>
> > >> f=: 1 2 1&p.
> > >> g=: 1 3 3 1&p.
> > >> x=: 10%~i=: i.8
> > >> ]c=: (f*g) t. i NB. This still has problems
> > >> 1 5 10 10 5 1 0 0
> > >
> > > What problems?
> > >
> > > 1 2 1 +//.@:(*/) 1 3 3 1
> > > 1 5 10 10 5 1
> > >
> > > Thanks,
> > >
> > > --
> > > Raul
> > > ----------------------------------------------------------------------
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