Sorry if my question is a duplicate of Trying To Obtain Fourier Cosine Coeficients of A Set of data But I did not find a decent solution there.
I’m trying to find Discrete Fourier transform on my set of data (attached as diff.txt file). I’ve tried queries:
“Fourier decomposition” and “FourierDCT”. “FourierDCT” should work, but it says, ‘Assuming “FourierDCT” is referring to a Wolfram Language function | Use as a math function instead’ (fourier_dct.png). When I go to link under words “math function” I get fourier_dct_math_function.png.
Thanks for your reply, Ilya!
I kind of know, that I am writing my request in a wrong form. I just want to know how to write it right.
First of all, unfortunately, I don’t have Mathematica, my question is about Wolfram Alpha only.
Second, I already tried what you suggested - please see my attached screenshot for details. Downloaded file is called “c.txt”.
Third, I failed to watch your file “FourierDCT.nb” in my CDF player (version 9.0.2.0).
Error message is,
FourierDCT::fftl: “Argument !\"-1.000000000000000000e+00 0.000000000000000000e+00\\\\n-9.949874686716791983e-01 0.000000000000000000e+00\\\\n-9.899749373433583965e-01 0.000000000\" \[Ellipsis] \"3433581745e-01 2.958823122697410227e-02\\\\n9.949874686716790873e-01 2.215147684345047940e-02\\\\n1.000000000000000000e+00 1.559357775423273439e-02\" is not a non-empty list or rectangular array of numeric quantities.”
Could you please save it in some sort of compatibility mode?
I guess the data in file diff.txt is not in a proper format. I’m not that acknowledged in this spehre of math, you know. But Mathematica keeps giving me the same error reply:
FourierDCT::fftl (then it’s listing arguments from file) is not a non-empty list or rectangular array of numeric quantities.
If u haven’t tried, u can read this article for help Discrete Fourier Transforms
P.S I’ve tried running an example and it works perfect
Hope I’ve helped you a little bit. And if u solve your problem, I’ll be glad to know the answer 