How sorting works in PHP? What algorithm is used?

Question

How PHP asort() works? What algorithm is used for sorting? I am using asort() function to sort an $array but its not sorting as i wanted.

<?php
  $array = array("test","Travel","en");
  asort($array);
  var_dump($array); "test" }
?>

The var_dump() gives

array(3) { 
    [1] => string(6) "Travel" 
    [2] => string(2) "en" 
    [0] => string(4) "test" 
}

The algorithm used is a quicksort: see the Note in the PHP Docs... and it's case-sensitive by default, so that's why Travel with an upper-case T comes before en with a lower-case e — Mark Baker
– Mark Baker, Commented Jan 12, 2017 at 17:20

miken32 · Accepted Answer · 2017-01-12 17:25:00Z

2

Use flags to change the case sensitivity of the asort() function.

$array = ["test", "Travel", "en"];
asort($array, SORT_FLAG_CASE | SORT_NATURAL);
var_dump($array);

These are documented with the sort() function.

answered Jan 12, 2017 at 17:25

miken32

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Comments

Suchit kumar · Accepted Answer · 2017-01-12 17:25:13Z

1

you can try if natcasesort(case insensitive) you want to sort in natural order:

<?php
  $array = array("test","Travel","en");
  natcasesort ($array);
  var_dump($array);

answered Jan 12, 2017 at 17:25

Suchit kumar

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rocky · Accepted Answer · 2017-01-12 17:35:23Z

0

Firstly, PHP uses an implementation of Quicksort
Secondly, For more information go through http://php.net/sort

Note: agree with @miken32 answer

answered Jan 12, 2017 at 17:35

rocky

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