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MatLab TideAnalyser

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The MatLab program TideAnalyser analyses a water level matrix timeseries(i.e., a matrix i cells by j cells by t time) and outputs a harmonic analysis matrix.

It is availiable through SourceSafe OtherTools database.

Sample Output from TideAnalyser: S2 Amplitude from MOHID, forced with FES2004
Sample Output from TideAnalyser: S2 Phase from MOHID, forced with FES2004

Description

The program TideAnalyser reads a MOHID HDF5 and returns harmonic component analysis for the entire netcdf waterlevel matrix, writing jpg files to an output directory.

Requirements

It requires a MOHID HDF5 file. If you have a netcdf file, you can change the code easily in a way that there is a variable named 'data' which has dimensions ixjxt.

Data Input

If called simply without arguments, it will ask you the data:

- a MOHID HDF5 file with water level data,

- an output directory,

You can specify the input manually by entering them in the following way:

 tideanalyser('file')

Output

The program will write an TA_data.mat file to the output directory that includes:

- TA_data.mat: the amplitude and phase matrix which is has dimensions ixjxh, with the harmonic components as h.

And it will write in the output directory:

- JPG/PNG files: containing the amplitude and phase maps for each harmonic analysed.

Remarks

Execution time

The program takes 3hours to analyse a 250*436*736 matrix, mainly due to harmonic analysis on each cell using T_TIDE package.

T_TIDE: Tide analysis

A t_tide package has to be installed in order to use this script.

The 'T_TIDE' package from Rich Pawlowicz, can be obtained here. It is based on the classic FORTRAN tidal analysis packages written by Mike Foreman here.