  > you can compute any logarithm from two base-e ones.

They need not be base e. Any base will do as long as it is the same for both the numerator and the denominator

▲ purplesyringa a day ago | parent [-]

Yeah, I simplified it a little. Though I must say I'm surprised pretty much every library I looked at uses the natural logarithm specifically, and not log2, which would seemingly be easier to compute with floats. Does anyone here know why, by any chance?

	▲	AlotOfReading a day ago \| parent \| next [-]
		You can change base with a single multiplication by special constants if you accept 1ULP error, so working in one or the other doesn't really gain you much. But exp/logs are often implemented as a combination of a table lookup and polys, so you can just bake it into the constants even more easily.
	▲	stackghost a day ago \| parent \| prev [-]
		Not sure why they wouldn't use log2 internally, but the mathematical reason is that e^x is the function whose derivative is itself, so it and the natural logarithm are fundamental to lots of other theories/operations like Euler's formula.