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Digg  is_infinite
Finds whether a value is infinite
(PHP 4 >= 4.2.0, PHP 5)
Code Examples / Notes » is_infinitedavid @t nirvanis d@t org
If you have PHP lower than 4.2 you can simulate the behaviour: function is_infinite($value) { return (substr("$value",-3) == "INF"); } (tested on php 4.1.2) stangelanda
Actually any string ending in INF is more appropriate than any string beginning with INF. Since negative infinity evaluates to "-INF" but it is still infinite. However in either case the STRING "INF" is not infinite, only a float that converts to "INF" or "-INF" is infinite. A more appropriate function might be: <?php if (!is_defined('is_infinite')) { function is_infinite($val) { return (is_float($val) and ("$val"=='INF' or "$val"=='-INF')); } } ?> * However the above function is untested. 21-aug-2006 04:54
@ david, That will return true for any string ending with "INF". I think substr("$value",0,3) would be more appropriate. |
