Yuuki Hirano,
Eigenvalue problems of the biharmonic operator in
a square region ---
finite difference analysis of Chladni figures,
master thesis of Meiji University,
2012 March. (in Japanese)
,
MATLAB programs,
MATLAB programs tarball,
how to use programs
Brief instruction:
Download
plate_f1.m
and
plot_n.m.
Try
N=160
A=plate_f1(N,0.3);
[v,d]=eigs(A,200,0);
plot_n(v(:,201-4),N,N)
plot_n(1.535*v(:,201-7)+v(:,201-8),N,N)
N=160, Poisson's ratio=0.3, compute 200 eigenvalues and
eigenfunctions, draw the fourth eigenfunction v4 and
1.535*v7+v8