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sin.md

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Sin

  • Bhaskara I's sine approximation formula
    • https://twitter.com/KilledByAPixel/status/1668498488408014850

      • Today I learned about an approximation for sine discovered by Bhaskara in 600 CE. I am using it to fix tiny discrepancies with Math.sin in different browsers. Here's my code... #javascript #math #generativeart

      • Z=x=>(((x%=360)<0?x+=360:x)<180?4:-4)*(x=(x%=180)*(180-x))/(40500-x)

      • I should add this is LESS accurate then calling Math.sin(), with a maximum error of about 1.8% But it's small enough to not be visually noticeable, and for my use case the more important thing is that the results are exactly the same in different environments.

      • Very nice! Consider also replacing ((x%=360)<0?x+=360:x)<180 with (x=(x%360+360)%360)<180 or (depending on input range) (x=(x+36e3)%360)<180.

      • Very tiny errors that can add up with some algorithms to eventually produce big differences in generative artwork. I am not sure why the cause but my guess is a slightly different size lookup table or slightly different method of interpolation.