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Bug #73641 ceil function not work fine in special float number
Submitted: 2016-12-02 09:29 UTC Modified: 2016-12-02 11:12 UTC
From: ufomoujie at gmail dot com Assigned:
Status: Not a bug Package: Unknown/Other Function
PHP Version: 5.6Git-2016-12-02 (Git) OS: windows10
Private report: No CVE-ID: None
View Developer Edit
 [2016-12-02 09:29 UTC] ufomoujie at gmail dot com 
Description:
------------
PHP 5.6.24 (cli) (built: Jul 20 2016 21:18:30)
Copyright (c) 1997-2016 The PHP Group
Zend Engine v2.6.0, Copyright (c) 1998-2016 Zend Technologies

script:

$value = 16.1 * 1000;
$iValue = ceil($value);
var_dump($value, $iValue);

result :

float(16100)
float(16101)

expect:

float(16100)
float(16100)


Test script:
---------------
$value = 16.1 * 1000;
$iValue = ceil($value);
var_dump($value, $iValue);

Expected result:
----------------
float(16100)
float(16100)

Actual result:
--------------
float(16100)
float(16101)

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 [2016-12-02 11:12 UTC] requinix@php.net
-Status: Open +Status: Not a bug
 [2016-12-02 11:12 UTC] requinix@php.net 
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.
 
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