Re: XSL Documentation: a number is true when...

Play the video

Subject: Re: XSL Documentation: a number is true when...
From: Norman Gray <norman@xxxxxxxxxxxxxxx>
Date: Wed, 25 Jul 2007 11:14:12 +0100

Kai, hello.

On 25 Jul 2007, at 10:57, Kai Hackemesser wrote:

a number is true if and only if it is neither positive or negative zero nor NaN<<

My problem may be just lack of english language, but I need some explanation here. What is meant by positive or negative zero? From my math understandings zero is neither positive nor negative. If I drop that and say, a number is true when the value is neither zero nor NaN, would this be correct?

On essentially all significant hardware these days, floating point numbers are represented according to the IEEE 754 standard[1]. Amongst other things, that includes special bit patterns for positive and negative infinity, a large set of bit patterns for NaN (not-a- number), and the property that zero can be signed, so that 1.0*0.0= +0.0 and -1.0*0.0 = -0.0. The distinction matters in certain numerical contexts, but is ignorable for everyone else.

All the best,

Norman

[1] http://en.wikipedia.org/wiki/IEEE_754


--
------------------------------------------------------------
Norman Gray  :  http://nxg.me.uk
eurovotech.org  :  University of Leicester, UK

Current Thread
XSL Documentation: a number is true when... Kai Hackemesser - 25 Jul 2007 09:57:54 -0000 Norman Gray - 25 Jul 2007 10:14:30 -0000 <= Justin Johansson - 25 Jul 2007 12:36:10 -0000 Kai Hackemesser - 25 Jul 2007 13:25:15 -0000

<- Previous	Index	Next ->
XSL Documentation: a number i, Kai Hackemesser	Thread	Re: XSL Documentation: a numb, Justin Johansson
XSL Documentation: a number i, Kai Hackemesser	Date	Running transformations using, Michael Kay
	Month

PURCHASE STYLUS STUDIO ONLINE TODAY!

Purchasing Stylus Studio from our online shop is Easy, Secure and Value Priced!

Download The World's Best XML IDE!

Accelerate XML development with our award-winning XML IDE - Download a free trial today!

Subscribe in XML format

RSS 2.0
Atom 0.3

XML Editor - Download a 15 Day Free Trial Now >

See What's New in Stylus Studio >

Buy Stylus Studio - XML Editor - Now >