Bug #74133 [Com]: PHP function in_array() return wrong.
Edit report at https://bugs.php.net/bug.php?id=74133&edit=1
ID: 74133
Comment by: long dot it dot stu at gmail dot com
Reported by: long dot it dot stu at gmail dot com
Summary: PHP function in_array() return wrong.
Status: Not a bug
Type: Bug
Package: Arrays related
Operating System: Centos
PHP Version: 5.6.30
Block user comment: N
Private report: N
New Comment:
Hi team!. it's clearly. thanks for your feedback!.
Previous Comments:
------------------------------------------------------------------------
[2017-02-20 09:57:46] 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.
Oh, sorry, I mistook how the range() worked.
https://3v4l.org/Nb2iK
The values in the arrays aren't what you think because floating-point numbers aren't
always accurate. You could round each value in the array, or use count+array_filter instead, or do
something else.
https://3v4l.org/JK901
https://3v4l.org/r8Pq8
https://3v4l.org/dZq7U
------------------------------------------------------------------------
[2017-02-20 09:09:29] long dot it dot stu at gmail dot com
with function range(1, 1.9, 0.1) it return result under:
Array
(
[0] => 1
[1] => 1.1
[2] => 1.2
[3] => 1.3
[4] => 1.4
[5] => 1.5
[6] => 1.6
[7] => 1.7
[8] => 1.8
)
when i check in_array(1.7, range(1, 1.9, 0.1));
it return False;
But all item in array except 1.7 it return False.
in range(0, 0.9, 0.1) it resut too.
------------------------------------------------------------------------
[2017-02-20 08:20:13] requinix@php.net
None of those four values exist in either of those two arrays.
------------------------------------------------------------------------
[2017-02-20 06:29:15] long dot it dot stu at gmail dot com
Description:
------------
---
From manual page: http://www.php.net/security.globals
---
PHP function in_array() return False although it existing.
Test script:
---------------
<?php
$array_1 = range(1, 1.9, 0.1);
var_dump(in_array(1.7, $array_1));
array_2 = range(0, 0.9, 0.1);
var_dump(in_array(0.3, $array_2));
var_dump(in_array(0.6, $array_2));
var_dump(in_array(0.7, $array_2));
//=>it return false;
------------------------------------------------------------------------
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Edit this bug report at https://bugs.php.net/bug.php?id=74133&edit=1
Thread (5 messages)