Fantastic Quaternions - Numberphile
Why Hacker News recommends it
HN recommends it as the simplest, most approachable introduction to quaternions, useful for people working in games and robotics.
What it is
Numberphile's James Grime introduces quaternions, a type of number beyond the complex numbers, building up from real and complex numbers and explaining why they are useful.
Recommended by 3 HN commenters across 3 different months, 2016 to 2018.
What Hacker News said
Strong rec skapadia · 2016-04 · on “Calculus Learning Guide”
Kalid - also your explanation of complex numbers is absolutely amazing. Sure I could manipulate them by memorizing rules, but I never really knew what they meant or why they were important. I also love the Numberphile explanation of quaternions (building up from real to complex numbers, etc.) - [this video] -Sujan
Strong rec codesushi42 · 2018-09 · on “Quaternions: the Strange Numbers That Birthed Modern Algebra”
Numberphile's explanation of Quaternions is the simplest I have seen so far: [this video] Quaternions are very important to know if you are doing any kind of 3D math. For instance, game programming or SLAM for robotics.
Recommends Tempest1981 · 2018-10 · on “Visualizing quaternions: An explorable video series”
This video might be easier to grasp: Fantastic Quaternions - Numberphile [this video] It also helped me to have a use-case in mind —- a motivation. Like maybe using the accelerometer/compasss in your phone to perform image stabilization or AR.