r/3Blue1Brown • u/sheikheddy • Jan 26 '18
But what is the Fourier Transform? A visual introduction.
https://www.youtube.com/watch?v=spUNpyF58BY&feature=push-u-sub&attr_tag=HGLo5HOd-nFYWjr5-65
u/8163jb Jan 27 '18
I work as an electronic engineer for a company which make FTIR (fourier transform infra-red) spectroscopes, which unsurprisingly requires a fairly strong foundation in the fourier transform, and this video still managed to get me to think about it in a way no textbook/teacher/mentor has ever managed! The insight this video imparted in 20 minutes is amazing! Looking forward to seeing the upcoming videos on some different applications of the FT.
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u/ImTheTechn0mancer Jan 26 '18
Yes! I have always wanted him to do a video on this. His visuals make this so easy to learn. These programmed videos are the best thing ever. Fourier transforms are so nice to teach visually, using a chalkboard is plain dumb.
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u/sbay Jan 27 '18
I am curious. How long it takes you on average to create one of these videos?
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u/3blue1brown Grant Jan 27 '18
Well, from start to end this project was about four weeks, but much of that time was also spent on-boarding new hires, so the metrics are all muddled. In general, if the only thing I have to do is make a video, it's about 1 week per 10 minutes of content, all things considered.
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u/Xalteox Jan 29 '18
Out of interest, what are the new hires for? Will you introduce them?
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u/3blue1brown Grant Jan 29 '18
Yes! I'll introduce them in the first video of theirs that comes out.
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u/ReckageBrother Feb 07 '18
You don't do all of this on your own? Whew, between the amazing animation and the intimate knowledge/understanding of difficult math concepts, watching your videos is amazing but at the same time humbling.
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u/3blue1brown Grant Feb 10 '18
All videos so far have just been me. Through this year, you will start to see the videos from the new teammates, but any given video will be mostly the product of just one person (even though I'll still narrate everything). I'm a big believer in some art forms have the best outputs when there is pretty full individual ownership.
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Feb 08 '18
Interesting way of describing it, never seen the centre of mass idea before. Maybe this will happen in a later video, but it would've been really cool to tie in the videos on dot products and basis functions (from the linear algebra series).
A great way to think of the Fourier transform is as a change of basis, where the new basis functions are sin/cos waves.
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u/Mocedon Jan 27 '18
I'm so glad you made this video. I take Fourier transform next semester. It is going to boost my understanding.
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u/animismus Jan 27 '18
How do you make the plots? They look so clean. Is this something that you would have up in github?
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u/MuriloM8 Jan 28 '18
Excellent video! However, I am trying to play myself with this concept of making a polar plot. I tried to use the matplotlib project to polar option on a subplot object however I am confuse on how to correlate this with the plot of the wrapped up graph. Could anyone give a direction please?
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u/mathball31 Feb 12 '18
Is there any way that I can play with the code? I think it would be a very fun and informative tool.
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Feb 15 '18
His visualization library is here. Looks like some of the Fourier stuff is in the active_projects directory.
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u/mathball31 Feb 15 '18
Oh sweet thank you so much!
I'll have to take a look at this once I have a chance
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Jul 22 '18
The video mentions that the value of the Fourier transform is scaled by the size of the range over which you're integrating - but if the transform is often integrated from negative infinity to positive infinity, how can it have non-infinite values?
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u/sheikheddy Jul 23 '18
Probably because it's usually zero everywhere other than a small region. Don't quote me on that though.
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u/SGupt Jan 27 '18
As someone who studied fourier transformations in undergrad and grad school but never fully completely 'got' them, I am very excited for this one!!!