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For which models was 2^3>8?
04-05-2017, 11:34 AM
Post: #17
RE: For which models was 2^3>8?
(04-04-2017 10:26 PM)Thomas Okken Wrote:  
(04-04-2017 05:51 PM)Dieter Wrote:  The explanation is simple and straightforward: yx is calculated as ex · ln y.
So 2³ is not evaluated as 2·2­·2 – how far should this go? Up to the 4th power? the 5th? The 10th?

How about all the way? It's really quite efficient if you use exponentiation by squaring: x^n = (x^(n/2))^2 if n is even, and x*(x^((n-1)/2))^2 if n is odd; apply recursively or iteratively. The algorithm is O(log(n)). This is how Free42 gets 2^3=8 exactly, despite not using extended precision for intermediate results.

I'm guessing they didn't want to spend the probably very limited ROM/RAM space of the old models to handle special cases of powers like that.
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Messages In This Thread
For which models was 2^3>8? - Joe Horn - 04-04-2017, 05:03 AM
RE: For which models was 2^3>8? - Joe Horn - 04-04-2017, 12:17 PM
RE: For which models was 2^3>8? - pier4r - 04-04-2017, 05:20 PM
RE: For which models was 2^3>8? - Dieter - 04-04-2017, 05:51 PM
RE: For which models was 2^3>8? - Dave Britten - 04-05-2017 11:34 AM
RE: For which models was 2^3>8? - pier4r - 04-04-2017, 06:10 PM
RE: For which models was 2^3>8? - bshoring - 04-04-2017, 06:16 PM
RE: For which models was 2^3>8? - teenix - 04-05-2017, 07:50 AM
RE: For which models was 2^3>8? - bshoring - 04-05-2017, 06:08 PM
RE: For which models was 2^3>8? - Dieter - 04-04-2017, 07:18 PM
RE: For which models was 2^3>8? - Dieter - 04-04-2017, 07:53 PM
RE: For which models was 2^3>8? - bshoring - 04-04-2017, 10:14 PM
RE: For which models was 2^3>8? - Andres - 06-23-2020, 04:39 AM



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