In the real world, Zero is Zero is Zero. Inside a JavaScript interpreter, certain calculations (most notably `Math.pow()` functions) require the sign of the zero value to be taken into account.

Internally, an ECMA compliant interpreter must be able to distinguish between +0 and -0 although from a mathematical standpoint the values are identical. Where calculations involve the likelihood of +infinity and -infinity, the sign can affect the outcome, and so can the sign of the zero value. For example the reciprocal of a very small number.

We have quietly ignored the sign of a zero value where it would make no difference. There are some discussions where it becomes important and so the sign is retained here for illustrative purposes.

See also: | Infinity,
Math.pow() |

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JavaScript Programmer's Reference, Cliff WoottonWrox Press (www.wrox.com)Join the Wrox JavaScript forum at p2p.wrox.comPlease report problems to support@wrox.com© 2001 Wrox Press. All Rights Reserved. Terms and conditions. |