Re: fftw and derivative. once again

Started by Jerry Avins January 9, 2011
Yes. The -om^2 must be a mistake. Whatever, it's not enough to simply fidoodle the amplitudes. In addition, the phases have to be advanced by 90 degrees, and that implies a different delay for each spectral line. I have an intuitive feel for what the time derivative of a discrete sequence means, but I'm glad that I don't have to deliver a mathematical definition.