# Some Math Thing about HD

**URL:** <https://discourse.processing.org/t/some-math-thing-about-hd/48514>\
**Category:** Gallery\
**Created:** [May 7, 2026, 12:35pm UTC](https://discourse.processing.org/t/some-math-thing-about-hd/48514 "2026-05-07T12:35:08Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![seanc4s](https://avatars.discourse-cdn.com/v4/letter/s/e19adc/32.png) [@seanc4s](https://discourse.processing.org/u/seanc4s)\
**Post date:** [May 7, 2026, 12:35pm UTC](https://discourse.processing.org/t/some-math-thing-about-hd/48514/1 "2026-05-07T12:35:08Z")

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A sketch for some math thing about HD iterated system.

H: fast Walsh Hadamard transform

D: diag(±1)

GPT vibe coded the ideas up very nicely:

[https://editor.p5js.org/seanhaddps/full/um-DEnBEo](https://editor.p5js.org/seanhaddps/full/um-DEnBEo)