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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)
21 Nov 2024 07:59:00
Latency
3135
Level
1.18

Harmonics

Points count
6103276
First date
29 Apr 2011 19:11
Last date
21 Nov 2024 07:59

Click on following link to see data:

Harmonics Constatns
Comp # Period (day) Cos factor (m) Sin factor (m)
0 0.00000 1.13446E+0 0E+0
1 0.12877 8.56533E-5 -8.34569E-6
2 0.12886 2.01919E-4 1.83689E-4
3 0.12938 1.45582E-4 -1.05376E-4
4 0.14707 -1.17702E-4 3.25996E-5
5 0.16841 3.21062E-4 3.19916E-4
6 0.16857 -1.57113E-4 -1.13186E-3
7 0.17036 7.13314E-4 1.13529E-4
8 0.17052 -2.82872E-3 -1.3269E-3
9 0.17251 -1.04611E-3 1.14523E-3
10 0.17470 4.33046E-4 -2.52463E-4
11 0.19989 3.07275E-4 3.83489E-4
12 0.20545 8.01291E-4 -1.07169E-4
13 0.24966 -5.58767E-4 1.01649E-5
14 0.25000 3.59227E-4 3.30305E-4
15 0.25395 -6.61006E-4 -3.92689E-4
16 0.25431 -1.28203E-5 1.11926E-3
17 0.25631 9.59575E-5 -6.83501E-5
18 0.25667 -2.1802E-4 4.38826E-5
19 0.25876 4.71231E-4 -4.78612E-4
20 0.26122 -2.68562E-4 8.458E-4
21 0.33303 3.29711E-4 1.5391E-3
22 0.34071 1.06121E-3 -9.95289E-5
23 0.34135 6.22956E-4 -4.52532E-4
24 0.34502 -3.25818E-3 3.15717E-3
25 0.34943 1.07872E-5 3.22504E-4
26 0.48977 -1.14669E-4 9.43949E-4
27 0.49109 9.5978E-4 -1.50574E-4
28 0.49863 1.12137E-2 4.96829E-3
29 0.49932 -1.06454E-3 3.45278E-4
30 0.50000 -3.89035E-2 -4.06712E-2
31 0.50798 2.23301E-3 1.03061E-2
32 0.50924 2.16603E-3 -1.11004E-3
33 0.51606 -4.90936E-3 5.06888E-3
34 0.51679 2.52087E-3 4.64794E-3
35 0.51753 -4.04713E-1 3.07125E-1
36 0.51826 1.35381E-3 -6.62324E-3
37 0.52608 -2.0825E-2 1.54318E-2
38 0.52743 1.02206E-1 6.78613E-2
39 0.53632 1.56818E-2 1.26138E-2
40 0.53772 5.32208E-3 -1.55269E-2
41 0.54697 2.08908E-3 -4.3636E-3
42 0.54843 -1.76684E-3 -4.90114E-4
43 0.89909 8.94131E-5 2.61448E-4
44 0.92942 1.47532E-3 -1.47798E-3
45 0.93417 7.73804E-4 1.70979E-3
46 0.96244 -3.94054E-3 2.83709E-3
47 0.96696 3.01015E-4 -4.02497E-5
48 0.99185 -6.44376E-4 4.3113E-4
49 0.99455 1.92753E-3 4.02841E-4
50 0.99727 4.56734E-2 4.54236E-2
51 1.00000 5.16272E-4 2.06479E-3
52 1.00275 1.08886E-2 1.61552E-2
53 1.00551 -5.76949E-4 9.49144E-4
54 1.02954 -1.06652E-4 2.04634E-3
55 1.03472 1.68853E-3 -2.05675E-3
56 1.04061 3.18716E-4 -4.10754E-5
57 1.06951 -7.05697E-4 -1.33424E-3
58 1.07581 3.25093E-2 -7.72137E-3
59 1.11346 3.1487E-4 1.34774E-3
60 1.11951 -2.29005E-3 -5.14112E-3
61 1.16035 5.59521E-4 -7.46306E-4
62 1.16693 6.26953E-5 -5.13618E-4
63 1.21136 1.16815E-4 -2.09911E-4
64 13.66079 2.20191E-3 -8.62446E-3
65 14.76529 1.35494E-3 2.37878E-3
66 27.55455 4.1031E-3 1.43874E-2
67 31.81193 -1.87587E-2 2.45672E-3
68 182.62118 -4.60041E-2 5.27021E-2
69 365.25998 6.42612E-2 1.03717E-1
Mathematical Formula
Tide calculation 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

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