
Evenly distributing points on a sphere - Signez
http://extremelearning.com.au/evenly-distributing-points-on-a-sphere/
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extremelearning
Author here. So amazed to find that my blog post got featured on Hacker news.
Happy to answer any questions that I can! :)

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gerdesj
I've seen the phylotaxis thing before but was unaware of the rather lovely
Fibonacci Lattice. My maths is only Civ Eng grad level from >25 years ago but
even I can appreciate this stuff. Your writing style is very approachable and
well illustrated.

Thank you.

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extremelearning
Thanks for the kind words. I’m glad you found it interesting and useful.

I think one of the advantages of writing blog posts rather than academic
articles is that they are often more readable to a wider audience as the
authors can be a little less formal in tone, expand on things (including
copious illustrations), without worrying about space constraints.

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gerdesj
For me, your style of writing provides a very decent balance. I'm not a
scientist, nor engineer, mathematician or similar but I am a common (or
garden) variety of nerd!

Quite often I will plough through papers and some of the more challenging blog
posts that are linked here. A post like yours is challenging but only for the
right reasons. You avoid a too "chatty" and "pally" style and present facts
concisely but with a bit of context - enough to point amateurs in the right
direction.

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mrep
If you are interested in spherical math, you should check out google's S2
library [0] which uses hilbert curves to classify areas on a sphere. Here is
an overview of the cell hierarchy [1]

[0]: [http://s2geometry.io/](http://s2geometry.io/)

[1]:
[http://s2geometry.io/devguide/s2cell_hierarchy](http://s2geometry.io/devguide/s2cell_hierarchy)

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kjeetgill
For anyone who was scratching thier head about how a plane filling curve gets
mapped into a sphere; what S2 really does is project the sphere onto the six
sides of a cube _and then_ fill each face with a Hilbert Curve index.

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mrep
Lol and Holy shit! That totally explains why the s2 cell lengths vary based on
where they are located in one of the six faces (aka, sides of a cube) of which
the documentation does not explain clearly. I have spent many hours using this
library and your comment has explained so much of what I was confused about
it.

Thank you

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kjeetgill
I'm glad I could help! I just picked up that fun fact from recently.

You're going to get a kick out of:
[https://news.ycombinator.com/item?id=17765388](https://news.ycombinator.com/item?id=17765388)

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nayuki
A somewhat related article recently on the HN front page - "Generating random
points inside a sphere": [https://karthikkaranth.me/blog/generating-random-
points-in-a...](https://karthikkaranth.me/blog/generating-random-points-in-a-
sphere/) ;
[https://news.ycombinator.com/item?id=17688599](https://news.ycombinator.com/item?id=17688599)

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ianai
Couldn’t this be used to model qubit states? Ie calculating function values on
the resulting pairs.

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aj7
In 2D, this is the porno theater problem.

