Bug #75004 [Opn->Nab]: Certain floats * 100 type cast to int value one less then they should be

Edit report at https://bugs.php.net/bug.php?id=75004&edit=1 ID: 75004 Updated by: requinix@php.net Reported by: c dot m dot tatro at gmail dot com Summary: Certain floats * 100 type cast to int value one less then they should be -Status: Open +Status: Not a bug Type: Bug Package: *General Issues Operating System: ubuntu PHP Version: 7.1.7 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://www.floating-point-gui.de/ Thank you for your interest in PHP. Previous Comments: ------------------------------------------------------------------------ [2017-07-28 16:12:00] c dot m dot tatro at gmail dot com Description: ------------ PHP 7.1.7-1+ubuntu14.04.1+deb.sury.org+1 (cli) (built: Jul 7 2017 10:07:42) ( NTS ) Copyright (c) 1997-2017 The PHP Group Zend Engine v3.1.0, Copyright (c) 1998-2017 Zend Technologies with Zend OPcache v7.1.7-1+ubuntu14.04.1+deb.sury.org+1, Copyright (c) 1999-2017, by Zend Technologies echo (int) (66.74*100); // 6673 echo (int) (35.55*100); // 3554 echo (int) (34.12*100); // 3411 To get a larger list run: for ($i=0; $i<=1000; $i++) { echo (int) (((float)$i/100)*100) ."\r\n";} Test script: --------------- echo (int) (66.74*100); echo (int) (35.55*100); echo (int) (34.12*100); for ($i=0; $i<=1000; $i++) { echo (int) (((float)$i/100)*100) ."\r\n";} ------------------------------------------------------------------------ -- Edit this bug report at https://bugs.php.net/bug.php?id=75004&edit=1