#How to calculate sqrt(float)

23 messages · Page 1 of 1 (latest)

white bobcat
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Is there some good algorithm to calculate the sqrt of a float or double? (In CS)

junior kayak
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Like calculating sqrt 0.02?

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@white bobcat

white bobcat
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Yes

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Or maybe sqrt(19287.39)

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The input will be random

stable tide
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how precise do you want it to be?

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i derived one funny algorithm but its mostly just for a pen & paper calculation

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just so that you can approximate the number

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for anything actually precise you probably want more advanced existing methods

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and maybe a couple of newton's method to improve the result

stable tide
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(yes, im still proud of my approximation)

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let me write it on python to show how it

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and it can also be written somewhat fast because float bit manipulation

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it gets worse tho for larger and larger numbers

image.png
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you might think 0.03 away isnt that bad

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but it is

image.png
stable tide
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but whats also fun is that it can be expanded to nth root

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not just sqrt

white bobcat
stable tide
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wow okay no this little funny algorithm is shit then lmao

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uh