4 ms·

It's useful to test explanations on people unfamiliar with it. So in this spirit, I want to share: the sentence didn't explain it to me. After watching3Blue1Br

It's useful to test explanations on people unfamiliar with it. So in this spirit, I want to share: the sentence didn't explain it to me. After watching3Blue1Brown's video, I get it. So I can share with you what confused me: It's this part of the sentence: "average a bunch of points along that path". I know what averaging it, but I don't know what averaging "along a path" means. Also I was (wrongly) expecting the output of this function to be a real number - I just expect "energy" to be a number. Instead, here what we're doing is averaging complex numbers so the output is a complex number. What a complex energy means is left as an exercise to the reader. Here's my suggestion for a sentence that would have worked better for me: "To find the energy at a particular frequency, spin your signal around a circle at that frequency, and find the center of mass of the plot." Presumably then we have to take the distance from the origin to get an amount of energy.

xedrac 4y ago
3Blue1Brown's video is the best explanation I've ever seen.
julianeon 4y ago
Thank you, this is the epitome of a helpful comment and it helped me.
wardedVibe 4y ago
> I just expect "energy" to be a number. Instead, here what we're doing is averaging complex numbers so the output is a complex number. What a complex energy means is left as an exercise to the reader. They shouldn't be using the term energy, really. That should be reserved for the magnitude of the complex number (so re(z)^2+im(z)^2). You can write a complex number either as a real and imaginary part, or as a amplitude r (the distance you're referencing) and phase (the rotation from r+0im). > "To find the energy at a particular frequency, spin your signal around a circle at that frequency, and find the center of mass of the plot." As someone who's spent a lot of time with the subject, I like this better than the original.

xedrac 4y ago

3Blue1Brown's video is the best explanation I've ever seen.

julianeon 4y ago

Thank you, this is the epitome of a helpful comment and it helped me.

wardedVibe 4y ago

> I just expect "energy" to be a number. Instead, here what we're doing is averaging complex numbers so the output is a complex number. What a complex energy means is left as an exercise to the reader. They shouldn't be using the term energy, really. That should be reserved for the magnitude of the complex number (so re(z)^2+im(z)^2). You can write a complex number either as a real and imaginary part, or as a amplitude r (the distance you're referencing) and phase (the rotation from r+0im). > "To find the energy at a particular frequency, spin your signal around a circle at that frequency, and find the center of mass of the plot." As someone who's spent a lot of time with the subject, I like this better than the original.