|  support |  documentation |  report a bug |  advanced search |  search howto |  statistics |  random bug |  login
Bug #52892 Casting/rounding problem
Submitted: 2010-09-20 13:25 UTC Modified: 2010-09-20 17:09 UTC
From: vahe at spir dot me Assigned:
Status: Not a bug Package: *Math Functions
PHP Version: Irrelevant OS: Debian GNU/Linux 5.0.5 (lenny)
Private report: No CVE-ID: None
View Add Comment Developer Edit
Welcome! If you don't have a Git account, you can't do anything here.
You can add a comment by following this link or if you reported this bug, you can edit this bug over here.
Block user comment
Status: Assign to:
Bug Type:
From: vahe at spir dot me
New email:
PHP Version: OS:


 [2010-09-20 13:25 UTC] vahe at spir dot me
After adding 10 times 0.1 and casting it into int or flooring it return value is 0 
instead of 1.

Test script:
$a = 0.1+0.1+0.1+0.1+0.1+0.1+0.1+0.1+0.1+0.1;

print $a; // 1
print round($a); // 1
print (int)$a; // 0 instead of 1
print floor($a); // 0 instead of 1

var_dump($a); // float(1)


Add a Patch

Pull Requests

Add a Pull Request


AllCommentsChangesGit/SVN commitsRelated reports
 [2010-09-20 17:09 UTC]
-Status: Open +Status: Bogus
 [2010-09-20 17:09 UTC]
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:
Thank you for your interest in PHP.

PHP Copyright © 2001-2022 The PHP Group
All rights reserved.
Last updated: Mon Oct 03 05:05:53 2022 UTC