Fft on data points

Roofit and RooStats
1

hi, im a new root user and need some help! :slight_smile: i have some data points (ascii) from an oscilattion and try to find the frequency. ive installed the fft packages. can you give me some advices how to do a fft with this plot? i only find some fft tutorials with an histo.
thanks a lot!
on the picture you can see the oscilattion and my little macro

fourierschwingung.png1280×800 191 KB

2

http://root.cern.ch/root/html/tutorials/fft/index.html

3

hi,
but this tutorial works only for an histo, how can i do the fft with my tgraph, sry i dont get it :frowning:

4

http://root.cern.ch/root/html/TVirtualFFT.html
http://root.cern.ch/root/html/src/TH1.cxx.html#C_mUuE
http://root.cern.ch/root/html/src/TH1.cxx.html#IMMn3D
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