#46613 [Opn->Bgs]: 55.76 value wrong interpreted

ID: 46613 Updated by: pajoye@php.net Reported By: nylas2u at yahoo dot com -Status: Open +Status: Bogus Bug Type: MySQL related Operating System: Windows XP PHP Version: 5.2.6 New Comment: Floating point values have a limited precision. Hence a value might not have the same string representation after any processing. That also includes writing a floating point value in your script and directly printing it without any mathematical operations. If you would like to know more about "floats" and what IEEE 754 is, read this: http://docs.sun.com/source/806-3568/ncg_goldberg.html Thank you for your interest in PHP. Previous Comments: ------------------------------------------------------------------------ [2008-11-19 13:21:13] nylas2u at yahoo dot com I also whant to clarify that the value is tored in an mysql field, and from mysql operation seems to be correct but using php script i have this problem ------------------------------------------------------------------------ [2008-11-19 13:18:30] nylas2u at yahoo dot com Description: ------------ I have an apache+php+mysql server. If i store in one field this value : 55.76 and after that reapitly decreasing this value to zero, after the las decrease i never can make the value to be zero. I over verified my script it works in this way with any value like 12.28 even when using 55.76005 but never for 55.76 Reproduce code: --------------- Example : 55.76 - 10 = 44.76 44.76 - 33 = 11.76 11.76 - 11.76 = 1.17... * E-15 Expected result: ---------------- of course that expected result should be zero ------------------------------------------------------------------------ -- Edit this bug report at http://bugs.php.net/?id=46613&edit=1