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Date: Wed, 18 Feb 2004 11:23:44 -0600
From: Eric Rudd <rudd AT cyberoptics DOT com>
Subject: Re: C99 Functions Under Development and Checkout
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Eric Rudd wrote:

> I doubt that the timings are completely consistent, but I modified an 
> FFT test harness to take the 2-D FFT an array of NaNs, and got the 
> following for a 1024-by-1024 array on a 550-MHz Pentium 3: Valid 
> floats, 30 ms; NaNs, 1.06 s -- a ratio of 35.  On a 1.7-GHz Pentium 4 
> there was even more of a difference: valid floats, 11 ms; NaNs, 2.6 s 
> -- a ratio of over 200. 

I just noticed an error in my earlier message.  These timings were for a 
256-by-256 array, not 1024-by-1024.  I had started to run the big array, 
but the NaN computation was taking so long that I got impatient, killed 
it, and ran the smaller problem.

-Eric