On Sat, 18 Oct 2008 12:24:22 -0700 (PDT), "Steven G. Johnson"
<stevenj@[EMAIL PROTECTED]
> wrote:
>On Oct 17, 8:21 pm, Eric Jacobsen <eric.jacob...@[EMAIL PROTECTED]
> wrote:
>> I understand this. You seem to be arguing that because a bunch of
>> papers came to some conclusion that that conclusion must be true for
>> everyone, everywhere.
>
>No, I'm arguing that your claims of "substantial" advantages have no
>sup****t, and your examples of supposed advantages (lower memory for
>trig tables, more sequential access, reduced memory reordering) were
>demonstrably false. It is impossible to prove a negative, but since
>you are the one claiming substantial advantages, the burden of proof
>is on you, especially since people have tried and failed to
>convincingly demonstrate such advantages for 20 years.
>
>> Given that the two transforms are different, it would seem pretty
>> logical that the differences would lead to advantages one way or other
>> depending on different cir***stances.
>
>If you actually look in detail at the algorithms, they are in fact
>extremely similar. This is why people who have studied the problem in
>detail have concluded that there don't seem to be significant
>advantages one way or the other. You have yet to correctly identify
>one significant difference.
>
>I would be very happy to learn of a way to use the DHT to gain a
>substantial advantage over real-data FFTs. FFTs of real data are
>annoying asymmetric transforms and the diversity of data formats for
>their redundant complex outputs are a PITA. But unsup****ted claims of
>substantial computational or memory savings, which have proved false
>again and again for two decades, are not helpful.
>
>Regards,
>Steven G. Johnson
'Substantial' is in the eye of the beholder, and the context matters,
as I've tried to repeatedly explain. I'm not interested in going
down a road that seems to me to be clearly headed to the usual
semantic nit-picking.
I don't feel up to holding your hand or convincing you, since you seem
already convinced of the infallibility of your point of view. As I
said, I don't really have a dog in this hunt and I've not felt the
need to convince anyone of anything. I was merely offering a point of
view based on my personal experience. As usual, this being teh
intartubes and all, all opinions are offered and taken FWTW. Clearly
you're already comfortable with being an expert on this topic. I
welcome you to your own contentedness in that realm.
I will also say that I've given quite a few hints as to where one can
find certain advantages and under what conditions. If you don't find
yourself in those conditions, you may continue to not find an
advantage. As usual, YMMV.
Eric Jacobsen
Minister of Algorithms
Abineau Communications
http://www.ericjacobsen.org
Blog: http://www.dsprelated.com/blogs-1/hf/Eric_Jacobsen.php
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