for (j=0;j<ntot;j++) {
jj=j % N;
data2[j]=10.0*exp(-1.*SQR(jj-M)/SQR(N/8))*
(cos(2.0*pi*32*jj/N)+cos(2.0*pi*64*jj/N));
}
sp2.addlongdata(data2,hann);
spec=sp2.spectrum();
freq=sp2.frequencies();
// for (i=0;i<M+1;i++)
// System.out.printf(setw(20) << freq[i] << " " << setw(20) << spec[i]);