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by colejohnson66 1494 days ago
> In order to achieve increased math processing speed, Intel broke mathematics algorithms down into part algorithm and part lookup tables - that is instead of having mathematics algorithms complete the whole task (which is the logical way of doing things).

Can you expand on this? I thought all FPUs used lookup tables? Even the 8087 had them.

1 comments

I think fpus still do for things like trig functions. Doing it using a power series potentially gives bad results and takes a long time to get enough accuracy. I think it was pretty common to use lookup tables in various algorithms back then since it was way faster to do a memory access and then some interpolation or just a memory access than to do a bunch of calculations.