On Fri, Mar 4, 2016 at 3:00 PM, Søren Sandmann <[email protected]> wrote:
> On Wed, Feb 10, 2016 at 1:25 AM, <[email protected]> wrote: > >> From: Bill Spitzak <[email protected]> >> >> Simpsons uses cubic curve fitting, with 3 samples defining each cubic. >> This >> makes the weights of the samples be in a pattern of 1,4,2,4,2...4,1, and >> then >> dividing the result by 3. >> >> The previous code was using weights of 1,2,6,6...6,2,1. Since it divided >> by >> 3 this produced about 2x the desired value (the normalization fixed this). >> Also this is effectively a linear interpolation, not Simpsons integration. >> > > It is not true that the previous code used these weights because it only > ran for half the segments (it had += 2). The intention with the code was to > do both the 4 and the 2 weight in one loop, but for that to work a1 and a2 > would have to be updated, which the code didn't do. So it was indeed buggy, > and I think the new code is correct. > You are right, the old code did weights of 1,2,0,6,0,6,...,2,1. This would explain why it worked even when I removed normalization. There should be spaces before the parentheses in the SAMPLE() macros, > though. > Ok will fix.
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