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HEALPix

53 points by hyperific

by ahurmazda

1 subcomments

I recall when I first saw Ubers’s H3[1], it really reminded me of healpix (from grad school). I know the algorithm is different but similar problem space: “given a point on a sphere, assign it to a stable cell ID”
1. https://www.uber.com/us/en/blog/h3/

by kmaitreys

0 subcomment

I used healpy[1] once during my undergraduate years. It was a summer project to develop an algorithm to find void galaxies.
[1]: https://healpy.readthedocs.io/en/latest/

by sligbad

1 subcomments

Also very cool: Google's S2 geometry - https://s2geometry.io/
Used by https://catch.astro.umd.edu/

by sligbad

0 subcomment

Love the HEALPix scheme, super useful for indexing too (some similar characteristics to geohashes).

by xioxox

0 subcomment

See also HiPS maps, which map the sky onto ever finer HEALPix grids to allow zooming: https://aladin.cds.unistra.fr/hips/