

// signal
N=256;
n=rand(N,1);
n=n-mean(n);
f0=0;f1=.5;
a=(f1-f0)/N;
s=real(exp(%pi*%i*a*(0:N-1)'.^2));
x=s+1*n;

// spectrogramme
[tfr,t,f]=tfrsp(x);

exec("plot_tf.sci");
plot_tf(tfr,t,f);
