GRAVITY returns the constant acceleration of gravity CALL: g = gravity(phi); g = acceleration of gravity in m/s^2 phi = latitude in degrees (default 45 degrees) GRAVITY calculates the acceleration of gravity using the international gravitational formulae: g = 9.78049*(1+0.0052884*sin(phi).^2-0.0000059*sin(2*phi).^2); Edit GRAVITY.M to change default value for PHI. Example:% g = gravity See also wdensity
Extracts waveheights and steepnesses from data. | |
Transform a dir. spectrum to an encountered. (Used in spec2spec) | |
Transforms directional spectrum to wavenumber spectrum. | |
gives parameters in non-central CHI-TWO process for directional Stokes waves. | |
Return covariance function given a directional spectrum | |
Computes values of the quadratic transfer function E, for quadratic sea | |
Calculates (and plots) a JONSWAP spectral density | |
Translates from wave number to frequency | |
factor for transforming spectra to finite water depth spectra | |
setup all global variables of the RECDEMO | |
Scale spectral density so that the moments equals m0,m2. | |
Spectral simulation of a Gaussian sea, 2D (x,t) or 3D (x,y,t) | |
Transform of spectrum from wave no. to frequency (used in spec2spec) | |
Evaluates spectral characteristics and their covariance | |
Separates the linear component of the Spectrum | |
Calculates spectral moments from spectrum | |
Simulates a Randomized 2nd order non-linear wave X(t) | |
Estimates the moments of 2'nd order non-linear waves | |
Create or alter SPECTRUM OPTIONS structure. | |
Saddlepoint approximation of the crossing intensity for the quadratic sea. | |
creates a test case for a buoy measurement | |
Creates a test case for measurement time series | |
creates a test case for a surface elevation measurement | |
Transform of spectrum from frequency to wave no. (used in spec2spec) | |
Calculates a JONSWAP spectral density for finite water depth | |
Calculates a double peaked (swell + wind) spectrum | |
Computes transfer functions based on linear wave theory | |
Translates from frequency to wave number | |
Normalize a spectral density such that m0=m2=1 |
001 function g=gravity(phi) 002 % GRAVITY returns the constant acceleration of gravity 003 % 004 % CALL: g = gravity(phi); 005 % 006 % g = acceleration of gravity in m/s^2 007 % phi = latitude in degrees (default 45 degrees) 008 % 009 % GRAVITY calculates the acceleration of gravity 010 % using the international gravitational formulae: 011 % 012 % g = 9.78049*(1+0.0052884*sin(phi).^2-0.0000059*sin(2*phi).^2); 013 % 014 % Edit GRAVITY.M to change default value for PHI. 015 % 016 % Example:% 017 % g = gravity 018 % See also wdensity 019 020 % References: 021 % Irgens, Fridtjov (1987) 022 % "Formelsamling i mekanikk: 023 % statikk, fasthetslære, dynamikk fluidmekanikk" 024 % tapir forlag, University of Trondheim , ISBN 82-519-0786-1, pp 19 025 026 % history 027 % revised pab 06.01.2000 028 % - added phi and international gravitational formulae. 029 % - updated documentation 030 031 if nargin<1 |isempty(phi) 032 phi=45; 033 end 034 phi=phi*pi/180; % change from degrees to radians 035 036 g=9.78049*(1+0.0052884*sin(phi).^2-0.0000059*sin(2*phi).^2); 037 %g=9.80665000000; 038
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