WaveSpectraFun

[Hm0,Tm01,Tm02,Tp,fp,f,Syy]=WaveSpectraFun(input,fs,duration,nfft,h,heightfrombed,fmin,fmax,ftailcorrection,tailpower,mincutoff,maxcutoff,tailcorrection,dispout)

DESCRIPTION

Calculate wave properties from power spectral density

INPUT

input=importdata(‘h.mat’);

Load water depth (h)/surface elevation (Eta) data and rename it “input” in (m)

fs=10;

Sampling frequency that data collected at in (Hz)

duration=1024;

Duration time that data collected in input in each burst in second

nfft=2^10;

NFFT for Fast Fourier Transform

h=1;

Mean water depth in (m)

heightfrombed=0.0;

Sensor height from bed

fmin=0.04;

Minimum frequency for cut off the lower part of spectra

fmax=1;

Maximum frequency for cut off the upper part of spectra

ftailcorrection=1;

Frequency that diagnostic tail apply after that (typically set at 2.5fm, fm=1/Tm01)

tailpower=-4;

Power that diagnostic tail apply based on that (-3 for shallow water to -5 for deep water)

mincutoff=’off’;

Define if to cut off the spectra below fmin

mincutoff=’off’: Cutoff off

mincutoff=’on’: Cutoff on

maxcutoff=’off’;

Define if to cut off the spectra beyond fmax

maxcutoff=’off’: Cutoff off

maxcutoff=’on’: Cutoff on

tailcorrection=’off’;

Define if to apply diagnostic tail correction or not

tailcorrection=’off’: Not apply

tailcorrection=’jonswap’: JONSWAP Spectrum tail

tailcorrection=’tma’: TMA Spectrum tail

dispout=’on’;

Define to display outputs or not (‘off’: not display, ‘on’: display)

OUTPUT

Hm0

Zero-Moment Wave Height (m)

Tm01

Wave Period from m01 (second), Mean Wave Period

Tm02

Wave Period from m02 (second), Mean Zero Crossing Period

Tp

Peak Wave Period (second)

fp

Peak Wave Frequency (Hz)

f

Frequency (Hz)

Syy

Wave Surface Elevation Power Spectrum (m^2s)

EXAMPLE

[Hm0,Tm01,Tm02,Tp,fp,f,Syy]=WaveSpectraFun(water_pressure/(1000*9.81),10,1024,256,1.07,0.05,0.05,5,1,-5,'on','on','off','on')