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Title: adding uk locations
#11
mm, well, ok I added the harmonics and tested them. Confusion reigns :crazy:

From the UKHO website, Plymouth on 10/16 gives
1:15 0.7, 7:23 5.5, 13:35 0.7, 19:42 5.6

Using only the 4 harmonics in the book, I get
1:24 1.07, 7:32 5.51, 13:41 1.11, 19:47 5.55

Close in time I guess, but way off on the heights of the low tides. High tides seems ok.

There's a method to calculate additional harmonics from limited data, but when I use this method I get:
12:58 0.68, 7:06 5.9, 13:15 0.67, 19:23 5.97

Ouch, times are worse and the high tides are too high, but low tides are close.

Finally, I found an old harmonics file with Plymouth in it, and that one gives me
1:08 0.52, 7:02 5.66, 13:27 0.51, 19:17 5.71

Lows are off, but close. Times for the highs are wrong, though, off by 20-30 minutes. Not good.

So nothing comes close the UKHO's predictions. I would have been happy with only being off by a few minutes or a few tenth's of a metre, but I can't get that close. Unfortunately, mixing and matching doesn't work Smile

I'm not sure how to proceed. I'll have to ponder this and think about what to do.
 
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Messages In This Thread
[No subject] - by - September 22, 2008 07:14
[No subject] - by - September 23, 2008 21:34
[No subject] - by - September 28, 2008 10:23
[No subject] - by - September 28, 2008 11:42
[No subject] - by - October 9, 2008 05:57
[No subject] - by - October 10, 2008 10:31
[No subject] - by - October 14, 2008 14:44
[No subject] - by - October 14, 2008 16:47
[No subject] - by - October 15, 2008 08:24
[No subject] - by - October 15, 2008 15:55
[No subject] - by - October 16, 2008 13:07
[No subject] - by - October 16, 2008 16:38
[No subject] - by - October 16, 2008 18:01

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