Example of Fig 5.5
Coefficients for harmonic wave
function [F,a]=example55 % % Eof of signal and noise % % Generate signal data clf; n=34; m=20; u=linspace(0,2*pi,m); v=linspace(0,2*pi,n); [x,y]=meshgrid(u); for j = 1:n a(:,:,j) = 10*sin(x - 2*v(j)) + 10*randn(length(u)); surf(x,y,a(:,:,j)) ; colormap(gray);brighten(0.5); end for j = 1:n z(:,j) = reshape(a(:,:,j),[m*m 1]); end size(z) [eof,s,v] = svd(z,0); size(eof), size(v) subplot(2,1,1) plot(1:n,v(:,1),1:n,v(:,2),'--'); legend('EOF 1','EOF 2'); title(' Time coefficients for propagating wave') for j = 1:n a(:,:,j) = 10*sin(x)*sin(2*v(j)) + 10*randn(length(u)); end for j = 1:n z(:,j) = reshape(a(:,:,j),[m*m 1]); end [eof,s,v] = svd(z,0); size(eof), size(v) subplot(2,1,2) plot(1:n,v(:,1),1:n,v(:,2),'--'); legend('EOF 1','EOF 2'); title(' Time coefficients for stationary wave') print('-dpdf','-adobecset','-painters','example132.pdf'); return
ans = 400 34 ans = 400 34 ans = 34 34 ans = 400 34 ans = 34 34
