Timeline for Challenge: Computing the Fourier Series of a List Plot!
Current License: CC BY-SA 4.0
11 events
| when toggle format | what | by | license | comment | |
|---|---|---|---|---|---|
| Jun 3, 2021 at 21:49 | history | edited | Daniel Lichtblau | CC BY-SA 4.0 | added 2223 characters in body |
| Jun 3, 2021 at 16:51 | comment | added | Daniel Lichtblau | That's useful information. For one, it indicates that trigs are sensible to use, periodicity is present, etc. It also means you might get advice from people familiar with the acoustics of bowed string instruments (which is expertise I lack, to put it nicely). | |
| Jun 3, 2021 at 16:47 | comment | added | rdx | @DanielLichtblau - thanks - ultimately my goal is to analyse this sound wave from my violin to see what is going on. I might then investigate what happens at a particular transition note, though I still haven’t ironed out the details! I’m basically investigating/modelling the sound wave of my violin to see if I can make any interesting observations/comments. | |
| Jun 3, 2021 at 16:38 | comment | added | Daniel Lichtblau | If I saw correctly, that video is about Fourier integrals. Since you have data points, a discrete FT seems more appropriate. Maybe if you explained what is the underlying problem you wish to solve, someone could give better advice. I know how to do some things with the folded points I showed (e.g. smoothing), but the validity of such operations might be questionable. | |
| Jun 3, 2021 at 15:37 | comment | added | rdx | @DanielLichtblau - sorry to pester - just wondered if you had managed to make a breakthrough by any chance? | |
| Jun 3, 2021 at 14:59 | comment | added | Daniel Lichtblau | @bgodfrey (I sometimes have trouble finding things when I am the author.) What I usually try is a web search, and hope I get lucky with the phrases. "Mathematica irregular periodogram" (without the quotes) works in this case. Change "irregular" to "nonuniform" and it does not do so well. Tricky business. | |
| Jun 3, 2021 at 13:46 | comment | added | bbgodfrey | @DanielLichtblau How do you find functions like this (if you are not the author)? | |
| Jun 3, 2021 at 6:46 | comment | added | rdx | Ah ok. Would it be possible for you to show me what you mean and go all the way to the final FS please? Even if that FS is inaccurate and has to be cut at a certain point - e.g. is possible to add a 'slider' as in the example video? I'm still slightly new to Mathematica and would be really grateful for your help. Thanks! | |
| Jun 2, 2021 at 23:40 | comment | added | Daniel Lichtblau | It's not (quite) a Fourier series that I computed. A modification of the code in that resource function would give you an irregular Fourier transform though. Also you can try to refine the period using values near what I found. Once you have that you might get a better (though still irregular) FT from the folded time series. | |
| Jun 2, 2021 at 22:32 | comment | added | rdx | Thanks @Daniel Lichtblau - I get almost all of what you are saying. I think what you have done is determined the periodicity of the function and then simplified the data? Now, can we use this to do the Fourier series on? Thanks! | |
| Jun 2, 2021 at 22:25 | history | answered | Daniel Lichtblau | CC BY-SA 4.0 |