
The Best Square Root Method Algorithm - jfaucett
https://www.codeproject.com/articles/69941/best-square-root-method-algorithm-function-precisi
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BillBohan
I really wish this article had explained how each method works. It's going to
take me some time to analyze each method to see whether any of them are the
method I was taught in elementary school.

It extracts the square root to any desired precision one digit at a time and
it looks a lot like long division. In binary you get one bit at a time and
there is no guesswork so it goes pretty quickly.

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BillBohan
I found the method I was taught at
[https://en.wikipedia.org/wiki/Methods_of_computing_square_ro...](https://en.wikipedia.org/wiki/Methods_of_computing_square_roots)
under the heading Digit-by-digit calculation.

It does not appear that this matches any of the methods tested. A long time
ago I implemented it in assembly for integers. It should be possible to write
a floating point version but my programming experience has been in embedded
systems and I never needed floating point. I would need to study floating
point representation but don't have much interest.

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anonymous_iam
I did a similar comparison last year, but mine was for an embedded system with
no FPP (MSP430). I was able to shave more than half of the average execution
time compared to the (highly optimized TI) math library function. The only
drawback to my method was that it would fail for input values greater than
255. Fortunately my application was guaranteed to never supply an input value
greater than 240.

