Oli Glaser wrote:
> On 07/06/2011 21:05, RNGolding@aol.com wrote:
>  =20
>> So far so good, however the sine waves have some jitter so I thought I
>> would take the average of a few consecutive phase measurements. That is =
 where
>> I come unstuck, how do you average phase readings?
>>
>> To illustrate the problem, if the phase is jittering about zero  degrees
>> giving 4 phase readings of say, 358, 359, 1 and  2 degrees, a simple ave=
rage
>> calculation yields 180 deg, which is  obviously wrong. Does anyone know =
how
>> calculate the true average,  which  should be 0 degrees? I'm sure the an=
swer
>> is obvious, but it has defeated me so  far.
>>    =20
>
> Not thought this through very carefully but...
> What about not wrapping to 0 after 360? (i.e unwrapping the phase)
> So you just keep going, and then after you average the readings you mod=20
> by 360 to get the result.
> So if you have 358, 359, 360, 361, 362. You get an average of 360, then=20
> 360 % 360 =3D 0
> Or if 178,179,180,181,182 -> 180 % 360 =3D 180.
> Or 720,721,722 -> 721 % 360 =3D 1
>
>
>  =20
How do you get it to count to 361, rather than having it stop at 1?

Kerry

--=20
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