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Fourier series visualisation with D3.js
- RobinL 13y agoAmazing how little code is needed to make this!
- cturhan 13y agoWow, that's awesome. Speaking of fourier, you need to see this http://en.m.wikipedia.org/wiki/File:Fourier_transform_time_and_frequency_domains.gif http://en.m.wikipedia.org/wiki/File:Fourier_transform_time_a...
- boyaka 13y agoOh yeah, I ignored this at first because I just saw wikipedia, but it's the same animation that was discussed in the other HN post.
- boyaka 13y agoJust in case anybody seeing this missed the post earlier: Article: https://news.ycombinator.com/item?id=7543691 https://news.ycombinator.com/item?id=7543691 Fourier Discussion: https://news.ycombinator.com/item?id=7544481 https://news.ycombinator.com/item?id=7544481 Direct link to Fourier animation: http://math.stackexchange.com/a/738048 http://math.stackexchange.com/a/738048 More advice from the discussion: http://betterexplained.com/articles/an-interactive-guide-to-the-fourier-transform/ http://betterexplained.com/articles/an-interactive-guide-to-...
- oamoruwa 13y agoAmazing. The real-time application of this is extremely powerful.
- ivan_ah 13y agoPowerful indeed. Imagine a lot of such "math demos" --- one for each equation/principle/concept in math. Instead of just the plot of a graph, you have a "toy" that you can play with. I never knew about <input type="range" ... but will be sure to play with it.
- oamoruwa 13y agoEmploying similar visualizations for other Numerical Methods would also be interesting to view.
- marcosscriven 13y agoReally nicely implemented
- maaaats 13y agofunction FT(A, N, φ) { φ = φ || 0; return function(x) { var n = -1, y = 0; while (++n < N) { y += A[n] * Math.sin(τ * (n + 1) * x + φ); } return y; } } hehe, seems annoying to type. Copy&paste everytime one of them is needed?
- deleted 13y ago[deleted]
- Kroem3r 13y agosearch and replace as the last launch step
- rbonvall 13y agoIn Vim using digraphs: Ctrl-K f * → φ Ctrl-K t * → τ In general: Ctrl-K <latin letter> * → <greek equivalent>
- pseut 13y agoI love Vim's digraphs! In emacs it's C-| tex then \phi → φ etc, which can be quite a bit more typing but can be easier to remember if you already know the TeX instructions for everything. Now we just need to convince other editors to add something similar...
- mickeyp 13y agoI think you mean C-u C-\ and then change the input type to tex. There are other ways of inputting digraphs: C-x 8 RET lets you enter the name of any unicode symbol. I wrote about the many ways of inputting digraphs and unicode here: http://www.masteringemacs.org/articles/2010/10/13/diacritics-in-emacs/ http://www.masteringemacs.org/articles/2010/10/13/diacritics...
- pseut 13y agoYou're right, thanks. But C-u doesn't seem to be necessary, unless I have a strange setup.
- kzrdude 13y agoThe sawtooth wave seems more pathological than it should be.
- surfnerd 13y agoIt's amazing.. very simple code !
- RachelF 13y agoImpressive stuff!
- BrandonMarc 13y agoreally impressive. note, if you accidentally add a / in one of the input fields, it gets a bit wonky and only refresh will repair it.
- QuixoticChris 13y agoThis is incredible. The linked circles perfectly illustrate how complex functions can be constructed from many superimposed sine waves. I'm very happy with this new knowledge! :)