#43267 [Opn->Bgs]: Error in Floating Point Operation

ID: 43267 Updated by: johannes@php.net Reported By: armadillo at penguinfriends dot org -Status: Open +Status: Bogus Bug Type: Math related Operating System: CentOS PHP Version: 5.2.5 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: ------------------------------------------------------------------------ [2007-11-12 18:30:02] armadillo at penguinfriends dot org Description: ------------ The is a bug in many php versions with a floating point operation. Tested PHP-Versions: 4.4.1 (Debian Sarge (3.1)), 5.0.4 (OpenSuse 10.0 x86_64), 5.2.5 (CentOS 5). It is a conversion from float to int, which doesn't work correct. See the reprocedure code and the expected result for more. When running it on the ssh-console on CentOS 5, on the native login console, the following output will be generated: setitimer: php (pid = 2731) provided invalid timeval it_value: sec = -1 tv_usec = 0 Hope this will help! ;) Reproduce code: --------------- <?php echo (int)(100*2.55); ?> Expected result: ---------------- 255 Actual result: -------------- 254 ------------------------------------------------------------------------ -- Edit this bug report at http://bugs.php.net/?id=43267&edit=1