Bug #53343 [Opn->Bgs]: iteration bug with variable assignation

Edit report at http://bugs.php.net/bug.php?id=53343&edit=1 ID: 53343 Updated by: rasmus@php.net Reported by: kanea at free dot fr Summary: iteration bug with variable assignation -Status: Open +Status: Bogus Type: Bug Package: *General Issues Operating System: w7 PHP Version: 5.3.3 Block user comment: N Private report: N 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: ------------------------------------------------------------------------ [2010-11-18 11:44:10] kanea at free dot fr Description: ------------ iterations give aproximation beetween two val, but . Every time there value are the same : 4.38 .. 10 Test script: --------------- for ($A = 0.8; $A < 5 * 3.1416; $A+=0.01) { echo $A."<br />"; } Expected result: ---------------- 0.08 0.09 ... 15.68 15.69 15.7 Actual result: -------------- 0.8 0.81 ... 4.36 4.37 4.38 4.3899999999999 4.3999999999999 ... 9.9899999999998 9.9999999999998 10.01 10.02 ... ------------------------------------------------------------------------ -- Edit this bug report at http://bugs.php.net/bug.php?id=53343&edit=1