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10/01/2015 9:19 am  #11


Re: Stripchart Advanced Channels - TWDPeriod and TWSPeriod

Duncan, yes, I got a little excited reading and then responding about the Fourier Transform. I am getting prepped now for short race to Mexico, this weekend, and will try to post an example afterwards from last week's w/l racing where we had some oscillations going on.  Cheers.

 

6/09/2016 9:21 am  #12


Re: Stripchart Advanced Channels - TWDPeriod and TWSPeriod

Nick, 

I am finally getting to use Exp on the water, and was just looking for something like this. In the Oakland Estuary, a windplot shows a major shift cycle of +.- 20-30 degrees about every 5 minutes, and on top of that a minor shift that could be +/- 10 degree ever 30 seconds. I was planning to log and analyze off line as a time series. 

If you return to the code, to manage 0/360 transition, May I request the ability to solve for :
baseline shift,  the first two dominant components, and to overlay that waveform on the actual measured TWD/TWS.

It would be perhaps very useful. That would of course then allow the mathematical projection of the next expected shift from the observed pattern...  and scalars of "Time to next shift" & "Next shift TWD/TWA/TWS/AWA/AWS"  and confidence/fit of pattern. 
 


Semiconductor Development Engineer, Retired Viticulturalist, Occasional sailor
"Lioness" 1962 Hinckley Bermuda 40 Custom Yawl
 

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