

Fast Inverse Square Root Function - Seems to have been created for Quake - dangoldin
http://www.scribd.com/vacuum?url=http://www.lomont.org/Math/Papers/2003/InvSqrt.pdf

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dangoldin
The PDF: <http://www.lomont.org/Math/Papers/2003/InvSqrt.pdf>

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pchristensen
It is at the point now where I click on the comments for every scribd.com
story to see if someone has pasted in the original pdf url. Never fails.

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dangoldin
I've noticed everyone likes the PDF version. It's trivial to add it as a
comment since I have it copied in the clipboard from creating the submission -
it's my standard practice now.

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notauser
Then why not submit the direct PDF link in the first place? Or is it a
'helpful' news.yc antifeature?

(PDF readers actually load faster than scribed, provided you aren't using the
vanilla Adobe one with all the plugins turned on.)

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dangoldin
It's a "helpful" feature. All PDF links are auto converted to scribd.

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xirium
It would be more useful if the original hyperlink to a PDF file was preserved
and a hyperlink to scribd was also presented. This would also eliminate a
problem with duplicate hyperlink suppression.

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apu
The history of this function: <http://www.beyond3d.com/content/articles/8/>

Finding the original author of the function (Greg Walsh):
<http://www.beyond3d.com/content/articles/15/>

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paulgb
If you just want the big picture, this link is easier to skim:

[http://betterexplained.com/articles/understanding-quakes-
fas...](http://betterexplained.com/articles/understanding-quakes-fast-inverse-
square-root/)

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mnemonicsloth
No. The "inverse square root function" is the "square function."

What you want is a function that gives the inverse of a square root.

Mathematical terminology sucks.

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etal
I was thinking the same thing.

    
    
      int inverse_square_root(int x) { return x * x; } // patent pending

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zenspider
great... now we can have all the posts that repeat every 3 months on
programming.reddit repeat here too! YAY for signal:noise.

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huhtenberg
Just don't upvote the submission. If it's a major dupe, it will get off the
front page very quickly.

