Faster Alternative to Math.sqrt()

javascript performance math math.sqrt
m-byte picture m-byte · Jan 1, 2017 · Viewed 8.2k times · Source

Are there any alternatives to using Math.sqrt() to get the square root of an unknown value?

For example:

var random  = (Math.random() * (999 - 1)) + 1;
var sqrt = Math.sqrt(random);

I've heard that using Math.sqrt() to get the square root of a number is a very slow operation, I'm just wondering if there are any faster ways I can get the square root of a random number. Any help with this would be greatly appreciated.

Answer

jony89 picture jony89 · Jan 1, 2017

You can be sure that the fastest algorithm you will write your self is already implemented within Math.sqrt if not better .

There is an algorithm to go through the numbers till the middle (with some simply calculation) : Writing your own square root function

but as I said, it's probably implemented if not better.

You can try to look for some specific business/domain logic in order to reduce numbers range .

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