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### Topic: Error in abs() documentation? (Read 631 times)previous topic - next topic

#### zlite

##### Jun 21, 2008, 06:32 am
The reference docs say that abs():

"Returns

x: if x is greater than or equal to 0.

-x: if x is less than 0. "

That's not the definition of absolute value as I understand it. I'm pretty sure it should be:

"Returns

x: if x is greater than or equal to 0.

x: if x is less than 0."

#### follower

#1
##### Jun 21, 2008, 07:40 am
If x is -1 then -x is -(-1) which is 1.

--Phil.

#### bens

#2
##### Jun 21, 2008, 08:59 am
Quote
"Returns

x: if x is greater than or equal to 0.

x: if x is less than 0."

This reduces to:

returns x

which would be fairly useless.

#### zlite

#3
##### Jun 21, 2008, 03:49 pm
My apologies, you're right--they mean the -(-1) = 1 formulation. It's just somewhat obscure and ambiguous phrasing for a very straightforward concept. But I suppose that's computer science for you ;-)

#### bens

#4
##### Jun 22, 2008, 10:57 am
It's basically the standard mathematical way to express what absolute value means.  The other way is |x| = sqrt(x^2).

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