fq.m

著名的seismiclab的代码 是地震学研究人员必备的工具

function [S,f] = fk(d,dt,dq,fmax);

[nt,nx]=size(d);

nf = 2*(2^nextpow2(nt));
S = fft(d,nf,1);

S = abs(S(1:nf/2,:));

f = (0:1:nf/2-1)/nf/dt;
 imax = floor(fmax*dt*nf) + 1;
S = S(1:imax,:);
Smax = max(max(S));

f = (0:1:imax-1)/nf/dt;
Smin = min(min(S));

S  = (S-Smin)/(Smax-Smin);


[I,J] = find(S<=0.0000001);
S(I,J) = 0.0000001;
S = log10(S);