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Old 2017-11-16, 21:39   #1
kruoli
 
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"Oliver"
Sep 2017
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Default Force FFT-size to be used

Hey,

I'm trying to execute non-PrimeNet-work like this (just as example):
Code:
PRP=N/A,1,2,1000000,51,99,0,3,1
PRP=N/A,1,2,1000000,35181,99,0,3,1
The first line will be executed with 64 K FFT, the second line with 100 K FFT. The bit sizes of the numbers are identical. The result is an extremely small round-off. Am I mistaken when I think that both of them should be able to use the same FFT? If so, how can one enforce a specific FFT size for an assignment or even the whole worktodo-file, if all the numbers have similar size?
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Old 2017-11-16, 23:20   #2
Batalov
 
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Mar 2008
Phi(4,2^7658614+1)/2

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You can enforce FFT size.
But you shouldn't - in this case.
Bitsize is not the only factor for the FFT size choice. The k and/or c value will affect the FFT size too. (In this case c value is large, 35181.)
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Old 2017-11-17, 15:31   #3
kruoli
 
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"Oliver"
Sep 2017
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The round-off is really small. Even then you should not decrease FFT-size?

Just out of curiosity: How do you set a specific FFT?
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Old 2017-11-17, 16:31   #4
ATH
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PRP=FFT2=64K,1,2,1000000,51,99,0,3,5

You should use type 5 PRP (the last 5 in the line) unless you are double checking a previous PRP result run with another type.

Edit: Nevermind I missed that it was not primenet work.

Last fiddled with by ATH on 2017-11-17 at 16:32
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Old 2017-11-17, 18:14   #5
kruoli
 
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Quote:
Originally Posted by ATH View Post
PRP=FFT2=64K,1,2,1000000,51,99,0,3,5
Nice, thanks! :)
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