At Mon, 15 Sep 2008 14:15:40 +0200, Simone Pigolotti wrote: > I just implemented the function *gsl_integration_qawf() *which I > need to calculate some Fourier integrals. I'm testing with some > simple example like the Fourier transform of a Gaussian function but > it is giving me problems: the result is correct exept for very small > frequencies, where the functions returns zero as a result (of course > the result of the integral of the distribution X cos(omega x) for > omega -> 0 should be 1). Is there any known problem with this > integration scheme? Or maybe I didn't set properly the parameters?
There are no known bugs in QAWF. The documentation gives a brief explanation of the algorithm, it integrates over segments of length pi/omega. This is probably the cause of what you are seeing because the gaussian will be almost zero over most of that range. I guess the function needs to be reasonably slowly varying over each region. If you think this could be handled better could you submit a bug report with a small example program showing the problem to [EMAIL PROTECTED], thanks. -- Brian Gough GNU Scientific Library - http://www.gnu.org/software/gsl/ _______________________________________________ Help-gsl mailing list [email protected] http://lists.gnu.org/mailman/listinfo/help-gsl
