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Ken Shirriff@kenshirriff@oldbytes.space (2026-09-27 02:02:02)
How do computers calculate complicated trig functions such as tangent? I took a look at Intel's 8087 floating-point chip under the microscope to find out. The chip combines two techniques to evaluate the tan function quickly and accurately: polynomials and an algorithm called CORDIC...
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Ken Shirriff@kenshirriff@oldbytes.space (2026-09-27 02:03:35)
Back in 1956, the Mach-2 B-58 Hustler had an analog navigation computer. It wasn't accurate enough, so they built a digital replacement. Sines and cosines are easy in analog, but required a new digital algorithm. They invented the CORDIC algorithm and built the 134-pound CORDIC computer.
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