Bug #72487 [NEW]: 100 - 99.6 why result = 0.400000001

From: wee_weerapat at hotmail dot com Operating system: Mac & Windows PHP version: 5.5.37 Package: PHP Language Specification Bug Type: Bug Bug description:100 - 99.6 why result = 0.400000001 Description: ------------ I'm not sure. 100-99.6 the result will return 0.400000001 and i try many case 100 - 99.96 the result still same 0.040000000000006 There return another position of number Test script: --------------- echo 100-99.6; echo "<br>"; echo 100-99.96; echo "<br>"; echo 1000-999.96; Expected result: ---------------- 0.4 0.04 0.04 Actual result: -------------- 0.40000000000001 0.040000000000006 0.039999999999964 -- Edit bug report at https://bugs.php.net/bug.php?id=72487&edit=1 -- Try a snapshot (PHP 5.4): https://bugs.php.net/fix.php?id=72487&r=trysnapshot54 Try a snapshot (PHP 5.5): https://bugs.php.net/fix.php?id=72487&r=trysnapshot55 Try a snapshot (trunk): https://bugs.php.net/fix.php?id=72487&r=trysnapshottrunk Fixed in SVN: https://bugs.php.net/fix.php?id=72487&r=fixed Fixed in release: https://bugs.php.net/fix.php?id=72487&r=alreadyfixed Need backtrace: https://bugs.php.net/fix.php?id=72487&r=needtrace Need Reproduce Script: https://bugs.php.net/fix.php?id=72487&r=needscript Try newer version: https://bugs.php.net/fix.php?id=72487&r=oldversion Not developer issue: https://bugs.php.net/fix.php?id=72487&r=support Expected behavior: https://bugs.php.net/fix.php?id=72487&r=notwrong Not enough info: https://bugs.php.net/fix.php?id=72487&r=notenoughinfo Submitted twice: https://bugs.php.net/fix.php?id=72487&r=submittedtwice register_globals: https://bugs.php.net/fix.php?id=72487&r=globals PHP 4 support discontinued: https://bugs.php.net/fix.php?id=72487&r=php4 Daylight Savings: https://bugs.php.net/fix.php?id=72487&r=dst IIS Stability: https://bugs.php.net/fix.php?id=72487&r=isapi Install GNU Sed: https://bugs.php.net/fix.php?id=72487&r=gnused Floating point limitations: https://bugs.php.net/fix.php?id=72487&r=float No Zend Extensions: https://bugs.php.net/fix.php?id=72487&r=nozend MySQL Configuration Error: https://bugs.php.net/fix.php?id=72487&r=mysqlcfg