Circles, Sines & Signals
Learning and science
interactive essay
SHOW HN2015
Legend
Circles, Sines & Signals
Interactive Essay on Signals, Sampling and the Fourier Transform
jackschaedler.github.io#fourier transform#signal processing#sampling#aliasing#interactive learning
How HN took it
22 positive, 7 neutral or asking, 4 mixed, 1 critical, out of 34 comments about the project. Thread score +0.61.
Idea: 11 for, 0 againstDocs: 3 for, 0 againstDesign: 3 for, 0 againstPerformance: 0 for, 1 againstPricing: 1 for, 0 against
The thread, comment by comment
Each row is a top-level comment and its replies, in HN's order. Select a cell to open that comment on HN.
positive neutral or mixed critical about another commenter or something else the maker
What HN said
What people liked
Clear, beautifully crafted interactive writing that beats static textbooks
From 4 comments
This is a wonderful piece of work. Exceptionally clear writing and excellent use of interactivity. One minor bug report, the mathematical pi symbol (U+1D6D1) used in the unit…
geographomics on HNThis is an _incredibly_ well-crafted piece of work. I mean -- my god -- the pressure wave animation? [1] 1: http://jackschaedler.github.io/circles-sines-signals/sound.html
gdubs on HNThis is simply beautiful
Sainth on HNThe dynamic visualizations are terrific here, I find that signals problems in textbooks are hard to understand when they are static. Awesome job!
dankoss on HN
Would have helped while learning the subject
From 2 comments
Normally I'd just upvote and move on, but this is really fucking good. For example, I wish I could have seen something like that "Sine Wave Aliasing" page when I was learning…
streptomycin on HNI wish they could have done things like this when I was learning signals and transforms as an undergrad. But interactive didn't really exist in the early 90s.
deitcher on HN
Objections
Site is slow in Firefox on the D3 animations
From 1 comment
The D3 animations work great for me in Chrome, but my Firefox is choking on them - especially this one.
protonfish on HN
MathJax equations fail to render over HTTPS
From 2 comments
It seems like the equation processing gets messed late in section 4 - $$ \mathrm{DFT}[k] = \sum_{n=0}^{N-1} \mathrm{x}[n] \cdot (cos(\varphi) - sin(\varphi)i) \\ where \quad…
jfoutz on HNThat's because you're accessing the site from HTTPS, or you have HTTPS Everywhere installed which is doing it for you. I think he's loading MathJax as HTTP, which means it gets…
Kronopath on HN
Unicode pi symbol not displayed in Chrome on Windows
From 1 comment
This is a wonderful piece of work. Exceptionally clear writing and excellent use of interactivity. One minor bug report, the mathematical pi symbol (U+1D6D1) used in the unit…
geographomics on HN
Requests
Add convolution and Dirac delta sections
From 2 comments
This is great! I'd love to see sections on convolution, the Dirac delta function, and the continuous (possibly multi-dimensional) Fourier transform.
calebreach on HNSeconded on convolution and the Dirac delta.
sbuccini on HN
Write more interactive articles and series on other topics
From 3 comments
This is great! Please write interactive articles on similar topics.
dm8 on HNThis is truly outstanding. I'd love to see an entire series done like this. Maybe you could Kickstarter this, and use it as a template for a series of DSP/Electronics/Physics…
TheOtherHobbes on HNThanks! Let me know if there are other topics you'd like covered, or areas that need more explanation.
jackschaedler on HN
Combine the articles into a single page instead of Next links
From 1 comment
Really great. One nitpick: I looked 10 seconds for "Next" link. Would be better as a single article IMO.
danabramov on HN
Questions
Was the interactive content written by hand or with a tool
From 2 comments
Did you use a tool to make the interactive diagrams, or just write all of them by hand? (I can imagine myself forever tweaking each diagram, and having to cut back on them, but…
CookieMon on HNHi Jack, awesome work! Did you write the HTML by hand or did you use or write some static generator? I'd love to have sidenotes like yours automatically generated and positioned.
rbonvall on HN
Alternatives named
Wolfram Demonstrations
From 1 comment
This is incredible. I wish more professors in universities incorporated this stuff in their teaching. I occasionally use Wolfram Demonstrations:…
shas3 on HN
Steven Wittens' quaternion animations
From 1 comment
I found this example by Steven Wittens to be remarkably well done: http://acko.net/blog/animate-your-way-to-glory-pt2/ See the section "Blowing up the Death Star" and note that…
malingo on HN