Tide Gauge Details - Tonga Island - Nukualofa_TO

Device description

Name
Tonga Island - Nukualofa_TO
Country
Tonga Island
Group
TD UNESCO
Lat/Lon
-21.136801 / -175.180695

Last measured values

Time(UTC)
02 Oct 2023 16:59:00
Latency
2837
Level
0.6

Harmonics

Points count
5520540
First date
29 Apr 2011 19:11
Last date
02 Oct 2023 16:59

Click on following link to see data:

Harmonics Constatns
Comp # Period (day) Cos factor (m) Sin factor (m)
0 0.00000 1.133E+0 0E+0
1 0.12877 8.2674E-5 -2.2928E-5
2 0.12886 2.16544E-4 2.1571E-4
3 0.12938 1.44364E-4 -1.13571E-4
4 0.14707 -1.18604E-4 5.44424E-5
5 0.16841 2.92931E-4 2.92874E-4
6 0.16857 -1.16543E-4 -1.18805E-3
7 0.17036 6.94811E-4 1.29377E-4
8 0.17052 -2.85411E-3 -1.36549E-3
9 0.17251 -1.00405E-3 1.15743E-3
10 0.17470 4.64444E-4 -2.41072E-4
11 0.19989 3.06841E-4 4.27898E-4
12 0.20545 8.37259E-4 -1.48314E-4
13 0.24966 -6.0782E-4 3.51173E-5
14 0.25000 4.04351E-4 3.48545E-4
15 0.25395 -7.12817E-4 -4.06642E-4
16 0.25431 3.25939E-5 1.17613E-3
17 0.25631 1.09388E-4 -8.78072E-5
18 0.25667 -2.29644E-4 5.79819E-5
19 0.25876 5.46589E-4 -5.49819E-4
20 0.26122 -3.22502E-4 9.37195E-4
21 0.33303 3.19585E-4 1.52811E-3
22 0.34071 9.80927E-4 -1.37933E-4
23 0.34135 6.59682E-4 -4.40206E-4
24 0.34502 -3.25742E-3 3.21603E-3
25 0.34943 -9.63038E-5 4.39101E-4
26 0.48977 -1.80071E-4 1.0423E-3
27 0.49109 1.05349E-3 -1.03041E-4
28 0.49863 1.04793E-2 4.58958E-3
29 0.49932 -1.24142E-3 2.93133E-4
30 0.50000 -3.86859E-2 -4.06479E-2
31 0.50798 1.78822E-3 1.02204E-2
32 0.50924 2.20718E-3 -1.0824E-3
33 0.51606 -4.88395E-3 5.80191E-3
34 0.51679 2.79567E-3 4.76964E-3
35 0.51753 -4.06499E-1 3.08208E-1
36 0.51826 1.13784E-3 -6.91937E-3
37 0.52608 -2.10148E-2 1.57597E-2
38 0.52743 1.02048E-1 6.79393E-2
39 0.53632 1.5914E-2 1.2636E-2
40 0.53772 5.25569E-3 -1.54248E-2
41 0.54697 1.97793E-3 -4.38853E-3
42 0.54843 -1.71015E-3 -4.8521E-4
43 0.89909 2.10144E-5 2.85218E-4
44 0.92942 1.38847E-3 -1.34356E-3
45 0.93417 8.76925E-4 1.72853E-3
46 0.96244 -3.94337E-3 2.80046E-3
47 0.96696 1.6506E-4 -5.53542E-5
48 0.99185 -7.254E-4 5.99621E-4
49 0.99455 2.09239E-3 5.68592E-4
50 0.99727 4.49142E-2 4.4638E-2
51 1.00000 5.43313E-4 1.93276E-3
52 1.00275 1.09011E-2 1.61373E-2
53 1.00551 -6.19686E-4 1.11128E-3
54 1.02954 -1.95159E-4 2.18333E-3
55 1.03472 1.5387E-3 -1.96866E-3
56 1.04061 3.82231E-4 4.52677E-6
57 1.06951 -6.4841E-4 -1.48917E-3
58 1.07581 3.16818E-2 -7.52251E-3
59 1.11346 2.61497E-4 1.4766E-3
60 1.11951 -2.33432E-3 -4.90237E-3
61 1.16035 5.71928E-4 -8.40163E-4
62 1.16693 1.09447E-4 -5.27582E-4
63 1.21136 1.30148E-4 -1.81627E-4
64 13.66079 2.59415E-3 -8.36577E-3
65 14.76529 1.27426E-3 1.86062E-3
66 27.55455 4.33035E-3 1.53795E-2
67 31.81193 -2.17756E-2 2.24791E-3
68 182.62118 -5.10518E-2 5.7943E-2
69 365.25998 6.66655E-2 1.07892E-1
Mathematical Formula
Visual Basic Syntax
Function EstimateTideValues() As [Function]
                        Dim Pi As [Double] = Math.PI
                        Dim sum As [Double] = harmonics(0, 1)
                        For k As Int16 = 1 To harmonics.GetUpperBound(0)
                        Dim period As [Double] = 2 * Pi / harmonics(k, 0)
                        Dim coefCos As [Double] = harmonics(k, 1)
                        Dim coefSin As [Double] = harmonics(k, 2) 
                        sum = sum + coefCos * Math.Cos(time * period)
                        sum = sum + coefSin * Math.Sin(time * period)
                        Next
                        Return sum
                        End Function
C# Syntax
double EstimateTideValues()
                        {
                        double Pi = Math.PI;
                        double sum = harmonics[0, 1];
                        for (int k=1; k <= harmonics.GetUpperBound(0); k++)
                        {
                        double period = 2 * Pi / harmonics[k, 0];
                        double coefCos = harmonics[k, 1];
                        double coefSin = harmonics[k, 2];
                        sum += coefCos * Math.Cos(time * period);
                        sum += coefSin * Math.Sin(time * period);
                        }
                        return sum;
                        }

Axis ranges

Start
End