#46879 [Opn->Bgs]: Float addition not always precise
| From: | derick@php.net | Date: | Tue, 16 Dec 2008 11:25:46 +0000 |
| Subject: | #46879 [Opn->Bgs]: Float addition not always precise | ||
| References: | 1 | Groups: | php.bugs |
| Request: | Send a blank email to php-bugs+get-132023@lists.php.net to get a copy of this message | ||
ID: 46879
Updated by: derick@php.net
Reported By: php at thwien dot de
-Status: Open
+Status: Bogus
Bug Type: Variables related
Operating System: Linux-Debian 4.0
PHP Version: 5.2CVS-2008-12-16 (snap)
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:
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[2008-12-16 11:24:06] php at thwien dot de
Description:
------------
Float comparison after addition isn't precise always.
Reproduce code:
---------------
$floatTotal = 19.99 + 39.99;
print ($floatTotal - 59.98);
Expected result:
----------------
0
Actual result:
--------------
7.105427357601E-15
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Edit this bug report at http://bugs.php.net/?id=46879&edit=1