[phobos] FFT

[David Simcha]

Ok, here's the code, I've got it down to about 800 milliseconds for a 
2^20 double[] -> Complex!double[] transform.  In comparison, the R 
statistics package, which is probably very heavily optimized and uses (I 
think) GCC as its compiler can do a similar transform in ~610 
milliseconds, so my code isn't blindingly fast, but it's not 
unreasonably slow.

On 8/1/2010 5:21 PM, Jason Spencer wrote:
> I don't have much of an opinion on adding to Phobos, but I'd definitely be
> interested in seeing the code.  I'm starting to do some scientific computing
> using D, and that would be a great learning reference for me.
>
> Jason
>
>
> ----- Original Message ----
>    
>> From: David Simcha<dsimcha at gmail.com>
>> To: Discuss the phobos library for D<phobos at puremagic.com>
>> Sent: Sun, August 1, 2010 1:32:38 PM
>> Subject: Re: [phobos] FFT
>>
>> Speed-wise, I've just been goofing around for the past hour or so and I've sped
>> it up 2x.  It now does 1 size 2 ^^ 20 double[] ->  Complex!double FFT in  about
>> 880 milliseconds.
>>
>> On 8/1/2010 3:36 PM, Walter Bright wrote:
>>      
>>>   David Simcha wrote:
>>>        
>>>> As I am no longer going to use FFTs  in my kernel density lib, improving
>>>>          
>> this FFT code will be bumped down my hacking  to-do list.  Does what I have now
>> sound better than nothing by a large  enough margin to warrant inclusion in
>> std.numeric, or does it sound too  primitive to be widely useful?  If it sounds
>> worth including I'll clean  up/document the code and send it to the mailing list
>> for review.  If it  sounds too primitive, I'll just scrap it.
>>      
>>>>          
>>> I don't  know enough about FFT's to make any sort of informed comment.
>>>   _______________________________________________
>>> phobos mailing  list
>>> phobos at puremagic.com
>>>   http://lists.puremagic.com/mailman/listinfo/phobos
>>>
>>>        
>> _______________________________________________
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>>
>>      
>    

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