




Fortran Programming Language









realft
Hi, I'm using realft from NR in fortran 77 to find the fourier transform of a real data. Can someone tell me how the output is arranged or how I have arrange it? many thanks, garba
On May 14, 9:04 am, garb@gmail.com wrote: > Hi, > I'm using realft from NR in fortran 77 to find the fourier transform > of a real data. Can someone tell me how the output is arranged or how > I have arrange it?
Have you read the recent thread in this newsgroup "fft from numerical recipes"? The poster found that the page "IDL and FORTRAN FFT Comparison" http://cimss.ssec.wisc.edu/~paulv/fft/fft_comparison.html answered his question.
On May 14, 9:47 am, Beliavsky <beliav@aol.com> wrote: > On May 14, 9:04 am, garb @gmail.com wrote: > > Hi, > > I'm using realft from NR in fortran 77 to find the fourier transform > > of a real data. Can someone tell me how the output is arranged or how > > I have arrange it? > Have you read the recent thread in this newsgroup "fft from numerical > recipes"? The poster found that the page "IDL and FORTRAN FFT > Comparison"http://cimss.ssec.wisc.edu/~paulv/fft/fft_comparison.html > answered his question.
Yes, I read that conversation repeatedly but still I'm missing something. What I actually wanted to do is to find the hilbert transform and when I plot my result, I'm getting is a kind of double plot. The shape is similar but a little bit displaced and the data points jump from a point in one of the plots to a point in the other plot. Does it have anything to do with the Nyquist frequency? thanks, garba





