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# array_multisort

(PHP 4, PHP 5)

array_multisort -- Сортировать несколько массивов или многомерные массивы

## Описание

bool array_multisort ( array ar1 [, mixed arg [, mixed ... [, array ...]]] )

Функция array_multisort() может быть использована для сортировки сразу нескольких массивов или одного многомерного массива в соответствии с одной или несколькими размерностями. Эта функция сохраняет соответствие между ключами и соответствующими им значениями.

Входные массивы рассматриваются как столбцы таблицы, которую нужно отсортировать по строкам - такой подход напоминает поведение выражения SQL ORDER BY. Первый массив имеет проиоритет в процессе сортировки.

Структура аргументов этой функции немного необычна, но удобна. Первым аргументом должен быть массив. Последующие аргументы могут быть как массивами, так и значениями, определяющими порядок сортировки, приведенными в нижеследующем списке.

Значения, определяющие порядок сортировки:

- SORT_ASC - сортировать в возрастающем порядке

- SORT_DESC - сортировать в убывающем порядке

Sorting type flags:

- SORT_REGULAR - сравнивать элементы обычным образом

- SORT_NUMERIC - сравнивать элементы, как если бы они были числами

- SORT_STRING - сравнивать элементы, как если бы они были строками

Недопустимым является указание двух флагов сортировки одинакового типа после каждого массива. Флаги сортировки, переданные после аргумента `ar1`, применяются только к этому аргументу - перед тем, как функция начнет обрабатывать следующий массив, эти флаги снова принимают значения по умолчаниюt SORT_ASC и SORT_REGULAR.

Возвращает `TRUE` в случае успешного завершения или `FALSE` в случае возникновения ошибки.

Пример 1. Сортировка нескольких массивов

`$ar1 = array ("10", 100, 100, "a"); $ar2 = array (1, 3, "2", 1); array_multisort ($ar1, $ar2);`

В вышеприведенном примере, после того, как будет осуществлена сортировка, первый массив будет содержать 10, "a", 100, 100. Второй - 1, 1, "2", 3. Элементы второго массива, соответствующие идентичным элементам первого (100 и 100), также будут отсортированы.

Пример 2. Сортировка многомерного массива

`$ar = array (array ("10", 100, 100, "a"), array (1, 3, "2", 1)); array_multisort ($ar[0], SORT_ASC, SORT_STRING, $ar[1], SORT_NUMERIC, SORT_DESC);`

В вышеприведенном примере, после сортировки, первый массив будет содержать 10, 100, 100, "a" (его элементы были отсортированы в возрастающем порядке так, как если бы они были строками), а второй массив будет содержать 1, 3, "2", 1 (элементы отсортированы как числа, в порядке убывания).

add a note User Contributed Notes
array_multisort
vermon7
27-Feb-2007 01:23
`When using array_multisort() on copies of arrays, it is changing all the copies, even if you modify the copy before using array_multisort().
I've avoided this bug by serializing a copy of array before calling array_multisort, and unserializg it after array_multisort() Look at the code:
<?php
$records_copy = serialize($records) ;
array_multisort ( $records[$sort_field] , $records[$sort2_field] ) ;
$records_copy = unserialize($records_copy) ;
?>`
Jon L. -- intel352 [AT] gmail [DOT] com
26-Feb-2007 08:27
`This is my solution for a dynamic multisort, using POST values. This doesn't account for a need to sort by multiple columns at once, but could be modified for that purpose.
<?php
/**
* @desc You really should validate the posted sort direction against a list of valid possibilities.
* Options are SORT_ASC, SORT_DESC, etc, as shown in the documentation for array_multisort
*/
$sort['direction'] = $_POST['sort_direction'] ? $_POST['sort_direction'] : 'SORT_ASC';
$sort['field'] = $_POST['sort_field'] ? $_POST['sort_field'] : 'value';
$array_to_sort = array();
$array_to_sort['TestCase1'] = array('name'=>'Test1','value'=>'218');
$array_to_sort['TestCase2'] = array('name'=>'Test2','value'=>'10');
$array_to_sort['TestCase3'] = array('name'=>'Test3','value'=>'64');
/**
* @desc Build columns using the values, for sorting in php
*/
$sort_arr = array();
foreach($array_to_sort AS $uniqid => $row){
foreach($row AS $key=>$value){
$sort_arr[$key][$uniqid] = $value;
}
}
print '<b>Before sorting</b>: <br> <pre>';
print_r($array_to_sort);
print '</pre>';
if($sort['direction']){
array_multisort($sort_arr[$sort['field']], constant($sort['direction']), $array_to_sort);
}
print '<b>After sorting</b>: <br> <pre>';
print_r($array_to_sort);
print '</pre>';
?>
This example prints out:
Before sorting:
Array
(
[TestCase1] => Array
(
[name] => Test1
[value] => 218
)
[TestCase2] => Array
(
[name] => Test2
[value] => 10
)
[TestCase3] => Array
(
[name] => Test3
[value] => 64
)
)
After sorting:
Array
(
[TestCase2] => Array
(
[name] => Test2
[value] => 10
)
[TestCase3] => Array
(
[name] => Test3
[value] => 64
)
[TestCase1] => Array
(
[name] => Test1
[value] => 218
)
)`
01-Dec-2006 06:58
`casting the parameter arrays for array_multisort seem to make the sorting ineffective?
for example:-
<?
foreach((array)$report_files as $report_files_i)
{
$file_stat = stat($report_files_i);
$report_files_x[] = array(
'filename' => $report_files_i
,'basename' => basename($report_files_i)
,'ctime' => date("D, M j, Y",$file_stat['ctime'])
,'size' => $file_stat['size']
);
$basename_i[] = strtolower(basename($report_files_i)); // case insensitive
}
array_multisort($basename_i, SORT_ASC, $report_files_x);
?>
The above works but if you change the last time to :-
<?
array_multisort((array)$basename_i, SORT_ASC, (array)$report_files_x);
?>
...adding the (array) cast doesn't sort the main array ...`
brettz9 throu gh yah
14-Sep-2006 12:04
`Often, one may have a group of arrays which have parallel data that need to be kept associated with each other (e.g., the various attribute values of a group of elements might be stored in their own arrays). Using array_multisort as is, by specifying additional fields, it is possible, as in the documentation example cited below, that this association will be lost.
To take this example set of data from the documentation:
<?php
$ar1 = array("10", 100, 100, "a");
$ar2 = array(1, 3, "2", 1);
?>
The example goes on to sort it this way:
<?php
array_multisort($ar1, $ar2);
?>
In this case, although the "10" remains associated with the first '1' after being sorted, the "2" and '3' are reversed from their original order.
In order to sort by one field only (yet still have the other array(s) being correspondingly sorted), one can use array_keys (which makes an array out of the keys) to ensure that no further sub-sorting is performed. This works because array_keys is making an array for which no duplicates can exist (since keys will be unique), and thus, the subsequent fields will have no relevance as far as subsorting.
So, using the above data, we can perform this sort instead:
<?php
$ar3 = array_keys($ar1);
array_multisort($ar1, $ar3, $ar2);
?>
which, when $ar1 and $ar2 are dumped gives:
array(4) {
[0]=> string(2) "10"
[1]=> string(1) "a"
[2]=> int(100)
[3]=> int(100)
}
array(4) {
[0]=> int(1)
[1]=> int(1)
[2]=> int(3)
[3]=> string(1) "2"
}`
ricardo
04-Sep-2006 05:47
`Hi,
Modded the function from KES,
goals:
- Object oriented
- string comparision using naturalordening
code:
<?
class HtmlTable{
var $sortorder;
var $rows;
//row adding stuf and constructor removed
function sort($sortorder){
if(is_array($sortorder)){
$this->sortorder=$sortorder;
usort($this->rows,array(&$this,'sort_compare'));
}
}
function sort_compare($a,$b){//sort function
$result=0;
foreach($this->sortorder as $key=>$value){
$result=strnatcmp($a[$key],$b[$key]);
if($result==0)continue;
if($value=='desc')$result=$result*-1;
break;
}
return $result;
}
}
?>`
LPChip
28-Aug-2006 06:04
`I was looking for a way to dynamically multisort my array.
By dynamically I mean that its not static what column will be sorted and if its ASC or DESC, and the ability to have more than one sorts.
This is the way a database would allow you to do.
The best way to dynamically do this, is by using eval.
The code below is partly what I used. (eg, I left out where the arrays were made and stuff, but the important part is here.)
<?
$orderby_arr = array("col1 ASC";"col2 DESC");
// prepare multisort using eval
$eval_sort = "array_multisort(";
if ($orderby !="") {
$orderby_arr_c = count($orderby_arr);
for ($orderby_walk=0; $orderby_walk < $orderby_arr_c; $orderby_walk++) {
$pos = strpos($orderby_arr[$orderby_walk], " ");
$orderby_col = substr($orderby_arr[$orderby_walk], 0, $pos);
$orderby_type = substr($orderby_arr[$orderby_walk], $pos+1);
$eval_sort .= "\$this->OrderBy[$orderby_col]" . ", SORT_$orderby_type,";
}
}
$eval_sort .= " \$this->Current_Query);";
// if there's an array, sort it.
if ($this->Current_Query_m != -1) eval($eval_sort);
?>`
RQuadling at GMail dot com
07-Aug-2006 05:53
`Extending KES's example (http://www.php.net/manual/en/function.array-multisort.php#68452) to look like array_multisort().
NOTE: Fully commented code is available at http://rquadling.php1h.com (sorry for the ads).
The syntax is the same as array_multisort().
You also have 3 additional parameters you can use:
AMC_SORT_STRING_CASELESS to sort the strings case insensitively.
AMC_LOSE_ASSOCIATION (the default behaviour) to lose the associations for the array.
AMC_KEEP_ASSOCIATION to keep the associations for the array.
Other than that, these function work together JUST like array_multisort but sorts using column(s) without the need to first extract the columns into individual arrays.
<?php
define ('AMC_SORT_STRING_CASELESS', SORT_STRING + 1);
define ('AMC_LOSE_ASSOCIATION', 1001);
define ('AMC_KEEP_ASSOCIATION', 1002);
define ('AMC_SORT_ORDER', 1003);
define ('AMC_SORT_TYPE', 1004);
function array_multisort_column(array &$a_data, $m_mixed1)
{
$a_Args = func_get_args();
$i_Args = func_num_args();
$GLOBALS['a_AMC_ordering'] = array();
$a_Columns = array_keys(reset($a_data));
$b_KeepAssociation = False;
for($i_Arg = 1 ; $i_Arg < $i_Args ; )
{
if (in_array($a_Args[$i_Arg], $a_Columns))
{
$s_Column = $a_Args[$i_Arg];
$GLOBALS['a_AMC_ordering'][$a_Args[$i_Arg]] = array
(
AMC_SORT_ORDER => SORT_ASC,
AMC_SORT_TYPE => SORT_REGULAR,
);
while
(
isset($a_Args[$i_Arg + 1]) &&
in_array
(
$a_Args[$i_Arg + 1],
array
(
AMC_KEEP_ASSOCIATION,
AMC_LOSE_ASSOCIATION,
AMC_SORT_STRING_CASELESS,
SORT_ASC,
SORT_DESC
SORT_NUMERIC,
SORT_REGULAR,
SORT_STRING,
),
True
)
)
{
if (in_array($a_Args[$i_Arg + 1], array(SORT_ASC, SORT_DESC), True))
{
$GLOBALS['a_AMC_ordering'][$s_Column][AMC_SORT_ORDER] = $a_Args[$i_Arg + 1];
}
elseif (in_array($a_Args[$i_Arg + 1], array(SORT_REGULAR, SORT_NUMERIC, SORT_STRING, AMC_SORT_STRING_CASELESS), True))
{
$GLOBALS['a_AMC_ordering'][$s_Column][AMC_SORT_TYPE] = $a_Args[$i_Arg + 1];
}
elseif (AMC_KEEP_ASSOCIATION == $a_Args[$i_Arg + 1])
{
$b_KeepAssociation = True;
}
++$i_Arg;
}
}
++$i_Arg;
}
$s_Sorter = ($b_KeepAssociation ? 'uasort' : 'usort');
$b_Result = $s_Sorter($a_data, 'array_multisort_column_cmp');
unset($GLOBALS['a_AMC_ordering']);
return $b_Result;
}
function array_multisort_column_cmp(array &$a_left, array &$a_right)
{
$i_Result = 0;
foreach($GLOBALS['a_AMC_ordering'] as $s_Column => $a_ColumnData)
{
switch ($a_ColumnData[AMC_SORT_TYPE])
{
case SORT_NUMERIC :
$i_ColumnCompareResult =
((intval($a_left[$s_Column]) == intval($a_right[$s_Column]))
?
0
:
((intval($a_left[$s_Column]) < intval($a_right[$s_Column]))
?
-1
:
1
)
);
break;
case SORT_STRING :
$i_ColumnCompareResult = strcmp((string)$a_left[$s_Column], (string)$a_right[$s_Column]);
break;
case AMC_SORT_STRING_CASELESS :
$i_ColumnCompareResult = strcasecmp((string)$a_left[$s_Column], (string)$a_right[$s_Column]);
break;
case SORT_REGULAR :
default :
$i_ColumnCompareResult =
(($a_left[$s_Column] == $a_right[$s_Column])
?
0
:
(($a_left[$s_Column] < $a_right[$s_Column])
?
-1
:
1
)
);
break;
}
if (0 == $i_ColumnCompareResult)
{
continue;
}
$i_Result = $i_ColumnCompareResult * (($a_ColumnData[AMC_SORT_ORDER] == SORT_DESC) ? -1 : 1);
break;
}
return $i_Result;
}
?>`
KES http://kes.net.ua
27-Jul-2006 05:30
`<?
//sort by second column then first one
$orderBy=array('0'=>'desc', 'first'=>'asc');
function KES_cmp($a, $b) {
global $orderBy;
$result= 0;
foreach( $orderBy as $key => $value ) {
if( $a[$key] == $b[$key] ) continue;
$result= ($a[$key] < $b[$key])? -1 : 1;
if( $value=='desc' ) $result= -$result;
break;
}
return $result;
}
$result= array();
$result[]= array( 'first'=>6, 2);
$result[]= array( 'first'=>3, 2);
$result[]= array( 'first'=>1, 3);
$result[]= array( 'first'=>1, 2);
$result[]= array( 'first'=>6, 1);
print "<b>Source</b>";
print_r($result);
usort($result, 'KES_cmp');
print "<b>Result</b>";
print_r($result);
?>`
KES
27-Jul-2006 04:35
`It is very handy to have function, which sort like this:
$arrayToSort[]= array(0 => ".", "type" => "dir");
$arrayToSort[]= array(0 => "qf", "type" => "file");
$arrayToSort[]= array(0 => "..", "type" => "dir");
$arrayToSort[]= array(0 => "text.txt", "type" => "file");
$arrayToSort[]= array(0 => "hello", "type" => "dir");
//first sort by the column 'type', then sort by the column '0'
$howToSort= array('type'=> 'asc', 0=> 'desc');
multisort($arrayToSort, $howToSort);
The result:
0 | type
----------------------------
. | dir
.. | dir
hello | dir
text.txt | file
qf | file`
Cesar Sirvent
17-May-2006 09:43
`There is a problem with array_multisort in languages other than English.
For special chars, as A with accent (Á), the sorting does not correspond to what might expect from a MySQL SELECT with ORDER BY.
For example
<?php
foreach ($students as $key => $row){
$surname[$key] = $row['surname'];
}
array_multisort($surname, SORT_ASC, $students);
?>
will sort the array in this way: ABADIA, ALVAREZ, BUÑUEL, ZUBIETA, ÁLVARES
while a MySQL SELECT with ORDER BY nombre ASC will yield
ABADIA, ÁLVARES, ALVEREZ, BUÑUEL, ZUBIETA
as A and Á are considered two different representations of the same letter.`
scott - evolove - net - work it out
22-Mar-2006 07:51
`A very simple way to sort an array of associative arrays by some value is to use usort.
I needed to sort an array of 20 data structures by their 'distance' value:
Array
(
[0] => Array
(
[blahblah] => blahblah
[distance] => 6
)
[1] => Array
(
you get the idea....
Here's the code:
--------------------
usort($results, "distributor_compare");
/**
* usort callback
*/
function distributor_compare($a, $b) {
$adist = intval($a['distance']);
$bdist = intval($b['distance']);
if ($adist == $bdist) {
return 0;
}
return ($adist < $bdist) ? -1 : 1;
}
--------------------`
peter dot graham at tcat dot ac dot uk
16-Feb-2006 07:16
`Many thanks to �AlberT at SuperAlberT dot it� for his useful and elegant function. I have made some small alterations so it doesn�t use pass-by-reference as this throws up warnings in newer versions of php4.
<?php
function array_key_multi_sort($arr, $l , $f='strnatcasecmp')
{
usort($arr, create_function('$a, $b', "return $f(\$a['$l'], \$b['$l']);"));
return($arr);
}
?>`
mail at theopensource dot com
31-Jan-2006 11:34
`I wanted to share with you a function that I created to make the array_multisort process much easier for myself... There was some interesting things that I encountered and I will post that in the comments.
I created this function so that all I have to do is tell it what column I want to sort through in a one level deep multidimensional array. You can Try this code in your browser to view the results
ex/
<?php
//Here is an array example
$test[0]['name'] = "David";
$test[0]['age'] = 28;
$test[1]['name'] = "Dennis";
$test[1]['age'] = 23;
$test[2]['name'] = "Joseph";
$test[2]['age'] = 42;
//Here is the Function
function sortmddata($array, $by, $order, $type){
//$array: the array you want to sort
//$by: the associative array name that is one level deep
////example: name
//$order: ASC or DESC
//$type: num or str
$sortby = "sort$by"; //This sets up what you are sorting by
$firstval = current($array); //Pulls over the first array
$vals = array_keys($firstval); //Grabs the associate Arrays
foreach ($vals as $init){
$keyname = "sort$init";
$$keyname = array();
}
//This was strange because I had problems adding
//Multiple arrays into a variable variable
//I got it to work by initializing the variable variables as arrays
//Before I went any further
foreach ($array as $key => $row) {
foreach ($vals as $names){
$keyname = "sort$names";
$test = array();
$test[$key] = $row[$names];
$$keyname = array_merge($$keyname,$test);
}
}
//This will create dynamic mini arrays so that I can perform
//the array multisort with no problem
//Notice the temp array... I had to do that because I
//cannot assign additional array elements to a
//varaiable variable
if ($order == "DESC"){
if ($type == "num"){
array_multisort($$sortby,SORT_DESC, SORT_NUMERIC,$array);
} else {
array_multisort($$sortby,SORT_DESC, SORT_STRING,$array);
}
} else {
if ($type == "num"){
array_multisort($$sortby,SORT_ASC, SORT_NUMERIC,$array);
} else {
array_multisort($$sortby,SORT_ASC, SORT_STRING,$array);
}
}
//This just goed through and asks the additional arguments
//What they are doing and are doing variations of
//the multisort
return $array;
}
//Now to test it
$test = sortmddata($test,'age','ASC','num');
print_r ($test);
//This will return
//Array (
//[0] => Array ([name] => Dennis [age] => 23 )
//[1] => Array ( [name] => David [age] => 28 )
//[2] => Array ( [name] => Joseph [age] => 42 )
//)
?>
There you go... please let me know what you think if you like.`
php a-t-the-r-a-t-e chir.ag
05-Jan-2006 02:10
`Re: phu at kungphu, 19-Dec-2005 11:36
asort($test) will not let me specify which columns to sort ASC/DESC, NUMERIC/STRING etc.
I have data similar to what you specified. Now I want to sort $test by points DESC and name ASC. Here's my function that does it, based on suggestions on this page. It uses array_multisort (and hence acts just like it: preserving string-keys etc.)
<?php
function arrayColumnSort()
{
$n = func_num_args();
$ar = func_get_arg($n-1);
if(!is_array($ar))
return false;
for($i = 0; $i < $n-1; $i++)
$col[$i] = func_get_arg($i);
foreach($ar as $key => $val)
foreach($col as $kkey => $vval)
if(is_string($vval))
${"subar$kkey"}[$key] = $val[$vval];
$arv = array();
foreach($col as $key => $val)
$arv[] = (is_string($val) ? ${"subar$key"} : $val);
$arv[] = $ar;
call_user_func_array("array_multisort", $arv);
return $ar;
}
$test["pete"]['points']=1;
$test["pete"]['name']='Peter';
$test["mike"]['points']=5;
$test["mike"]['name']='Mike';
$test["zoo"]['points']=2;
$test["zoo"]['name']='John Zoo';
$test["ab"]['points']=2;
$test["ab"]['name']='John Ab';
$test1 = $test;
asort($test1);
$test2 = arrayColumnSort("points", SORT_DESC, SORT_NUMERIC, "name", SORT_ASC, SORT_STRING, $test);
print_r($test1); // asort
print_r($test2); // arrayColumnSort
?>
Output from asort:
Array
(
[pete] => Array
(
[points] => 1
[name] => Peter
)
[ab] => Array
(
[points] => 2
[name] => John Ab
)
[zoo] => Array
(
[points] => 2
[name] => John Zoo
)
[mike] => Array
(
[points] => 5
[name] => Mike
)
)
Output from arrayColumnSort:
Array
(
[mike] => Array
(
[points] => 5
[name] => Mike
)
[ab] => Array
(
[points] => 2
[name] => John Ab
)
[zoo] => Array
(
[points] => 2
[name] => John Zoo
)
[pete] => Array
(
[points] => 1
[name] => Peter
)
)`
phu at kungphu
19-Dec-2005 11:36
`Notepad's example using asort/arsort will -not- work unless 'points' is defined -before- 'name'.
Running the posted code sorts by 'name', which was not the point of the previous posts. Defining 'points' as 'apoints' also did not work; however, defining 'points' first yields correct sorting:
$test[0]['points']=1;
$test[0]['name']='Peter';
$test[1]['points']=5;
$test[1]['name']='Mike';
$test[2]['points']=2;
$test[2]['name']='John';
asort($test);
It appears asort uses the first defined element to sort a multidimensional array.`
notepad at codewalkers dot com
09-Dec-2005 04:33
`for you guys trying to sort scores on an associative multi-dimensional array, why are you creating your own functions?
<?php
$test[0]['name']='Peter';
$test[0]['points']=1;
$test[1]['name']='Mike';
$test[1]['points']=5;
$test[2]['name']='John';
$test[2]['points']=2;
asort($test);
// or even arsort();
?>
the above seems to work for me...`
Shmee
30-Sep-2005 06:46
`RWC�s code works very well until you get a �point� value greater then ten. This is because the strcmp() function will return that 2 > 10 and 2 > 11 � 2 > 19 and so on. To compare number values over ten try a sort like this:
$test = multi_sort($test, $key = 'points');
function multi_sort($array, $akey)
{
function compare($a, $b)
{
global $key;
if ($a[$key]>$b[$key]){
$varcmp = "1";
return $varcmp;
}
elseif ($a[$key]<$b[$key]){
$varcmp = "-1";
return $varcmp;
}
elseif ($a[$key]==$b[$key]){
$varcmp = "0";
return $varcmp;
}
}
usort($array, "compare");
return $array;
}`
RWC
25-Sep-2005 01:45
`This is the simpler version of the function by AlberT.
A lot of times you have got an array like this:
$test[0]['name']='Peter';
$test[0]['points']=1;
$test[1]['name']='Mike';
$test[1]['points']=5;
$test[2]['name']='John';
$test[2]['points']=2;
You just want to sort on the index in the second dimension, ie. on points in the above example.
You can use the function below and call it like this:
$test = multi_sort($test, $key = 'points');
function multi_sort($array, $akey)
{
function compare($a, $b)
{
global $key;
return strcmp($a[$key], $b[$key]);
}
usort($array, "compare");
return $array;
}
Note: to be able to use $key in the compare function, it can not simply be passed as a parameter. It has to be declared global and set somewhere outside of compare().`
AlberT at SuperAlberT dot it
18-Jul-2005 06:59
`a nice piece of code to do an "array_key_multi_sort()" is the following:
<?php
/**
* orders a multidimentional array on the base of a label-key
*
* @param $arr, the array to be ordered
* @param $l the "label" identifing the field
* @param $f the ordering function to be used,
* strnatcasecmp() by default
* @return TRUE on success, FALSE on failure.
*/
function array_key_multi_sort(&$arr, $l , $f='strnatcasecmp') {
return usort($arr, create_function('$a, $b', "return $f(\$a['$l'], \$b['$l']);"));
}
?>`
kencomer at kencomer dot com
12-Jun-2005 11:48
`If your data is in an associative array that you would need to separate into columns such as those retrieved with your favorite flavor of _fetch_array() in order to be able to use multisort(), you should consider using uasort() or usort() as an alternative. Here is an example of how this could be beneficial:
(key is employee number which remains intact; rows are sorted by surname, firstname)
<?php
function namecmp( $row1,$row2 )
{
$first = strcmp($row1['surname'], $row2['surname']) ;
if ( $first )
return $first ;
else
return strcmp($row1['name'], $row2['name']) ;
}
$test = array( '11122202' => array('empno'=>11122202,'name'=>'geezer'
,'surname'=>'schmidt','age'=>96,'sex'=>'male')
,'11122204' => array('empno'=>11122204,'name'=>'coed'
,'surname'=>'beaujolais','age'=>18,'sex'=>'female')
,'11122206' => array('empno'=>11122206,'name'=>'immortal'
,'surname'=>'ramos','age'=>21,'sex'=>'male')
,'11122208' => array('empno'=>11122208,'name'=>'babyface'
,'surname'=>'brown','age'=>1,'sex'=>'male')
,'11122210' => array('empno'=>11122210,'name'=>'exjock'
,'surname'=>'gatti','age'=>48,'sex'=>'male')
,'11122212' => array('empno'=>11122212,'name'=>'jailbait'
,'surname'=>'muhammed','age'=>15,'sex'=>'female') )
;
echo "<pre>" ;
print_r( $test ) ;
uasort($test,'namecmp') ;
echo "----sorting----<br \>";
print_r( $test ) ;
echo "</pre>" ;
?>
Array
(
[11122202] => Array
(
[empno] => 11122202
[name] => geezer
[surname] => schmidt
[age] => 96
[sex] => male
)
[11122204] => Array
(
[empno] => 11122204
[name] => coed
[surname] => beaujolais
[age] => 18
[sex] => female
)
[11122206] => Array
(
[empno] => 11122206
[name] => immortal
[surname] => ramos
[age] => 21
[sex] => male
)
[11122208] => Array
(
[empno] => 11122208
[name] => babyface
[surname] => brown
[age] => 1
[sex] => male
)
[11122210] => Array
(
[empno] => 11122210
[name] => exjock
[surname] => gatti
[age] => 48
[sex] => male
)
[11122212] => Array
(
[empno] => 11122212
[name] => jailbait
[surname] => muhammed
[age] => 15
[sex] => female
)
)
----sorting----
Array
(
[11122204] => Array
(
[empno] => 11122204
[name] => coed
[surname] => beaujolais
[age] => 18
[sex] => female
)
[11122208] => Array
(
[empno] => 11122208
[name] => babyface
[surname] => brown
[age] => 1
[sex] => male
)
[11122210] => Array
(
[empno] => 11122210
[name] => exjock
[surname] => gatti
[age] => 48
[sex] => male
)
[11122212] => Array
(
[empno] => 11122212
[name] => jailbait
[surname] => muhammed
[age] => 15
[sex] => female
)
[11122206] => Array
(
[empno] => 11122206
[name] => immortal
[surname] => ramos
[age] => 21
[sex] => male
)
[11122202] => Array
(
[empno] => 11122202
[name] => geezer
[surname] => schmidt
[age] => 96
[sex] => male
)
)`
Michael Oelze at �M (myname) �T GMXdotDE
25-Apr-2005 09:15
`I try array_multisort at first and it seems to work well. But then I program a page with cached datas (the arrays were saved in a session). Suddenly the sort function doesn't seem to work. There was no error in my script, so I try the reference on the variables. Then he manage to sort the arrays again.
So it seems that if you save your Arrays in a session your arrays are global variables and then 'array_multisort' doesn't sort the arrays despite it gives back 'true'.
You must reference your variables and all work well:
session_start(); // restore variables (Arrays etc.)
.....
.....
array_multisort(&$Array1,&$Array2,&$Array3,...);
....
$_SESSION["Array1"]=$Array1;//
$_SESSION["Array2"]=$Array2;//Save Arrays in Session Data
$_SESSION["Array3"]=$Array3;//
......
Now you can store your Data Arrays in your Session and are able to sort them as you like...`
stevec at NO-/ dot /-SPAM dot qiguang dot net
13-Apr-2005 08:19
`Be careful when using array_multisort() on copies of arrays, as you might end up changing the original array. Given the following code:
<?php
$test1 = array(4,3,2,1);
$test2 = $test1;
$test3 = array('a', 'b', 'c', 'd');
array_multisort($test2, SORT_ASC, $test3);
echo 'test1:';
print_r($test1);
echo 'test2:';
print_r($test2);
echo 'test3:';
print_r($test3);
?>
You would expect:
test1:Array
(
[0] => 4
[1] => 3
[2] => 2
[3] => 1
)
test2:Array
(
[0] => 1
[1] => 2
[2] => 3
[3] => 4
)
test3:Array
(
[0] => d
[1] => c
[2] => b
[3] => a
)
However, if you run the code, you actually get:
test1:Array
(
[0] => 1
[1] => 2
[2] => 3
[3] => 4
)
test2:Array
(
[0] => 1
[1] => 2
[2] => 3
[3] => 4
)
test3:Array
(
[0] => d
[1] => c
[2] => b
[3] => a
)
Note that the original ($test1) ends up being sorted even though it was never called by array_multisort(). To work around this, insert a statement to modify the copy ($test2) before calling array_multisort() on it. The following code will produce the expected "correct" results:
<?php
$test1 = array(4,3,2,1);
$test2 = $test1;
$test3 = array('a', 'b', 'c', 'd');
$test2[0] = $test2[0]; // fix
array_multisort($test2, SORT_ASC, $test3);
echo 'test1:';
print_r($test1);
echo 'test2:';
print_r($test2);
echo 'test3:';
print_r($test3);
?>
This seems to be a resurrection of the closed bug #8130. Also, someone reported this behavior in bug #32031, but it was incorrectly labeled "bogus" in reference to bug #25359, which is a different issue.`
joao at intrasystems dot com dot br
07-Apr-2005 12:27
`Exemple of sorting multi-dimensional arrays by one of it's fields:
$result[0]['nome']='Joao';
$result[0]['order']=5;
$result[1]['nome']='Pedro';
$result[1]['order']=1;
$result[2]['nome']='Marcelo';
$result[2]['order']=3;
foreach($result as $res)
$sortAux[] = $res['order'];
array_multisort($sortAux, SORT_ASC, $result);
print_r($result);
produces:
Array
(
[0] => Array
(
[nome] => Pedro
[order] => 1
)
[1] => Array
(
[nome] => Marcelo
[order] => 3
)
[2] => Array
(
[nome] => Joao
[order] => 5
)
)`
Toni
10-Nov-2004 03:30
`An example to sort an array by 3 criteria:
$recordset is an array of results from a query to a database, that I sort using $matrix as auxiliary array. First numeric, Second and Third alphabetically.
<?php
for($idx=0;$idx<$toShow;$idx++){
$matrix[0][$id]=$recordset[$id][0];
$matrix[1][$id]=$recordset[$id][1];
$matrix[2][$id]=$recordset[$id][10];
}
array_multisort($matrix[0], SORT_DESC, SORT_NUMERIC,$matrix[1], SORT_STRING, SORT_ASC,$matrix[2], SORT_STRING, SORT_ASC);
?>`
meddle at dzygn.com
05-Oct-2004 07:40
`If you want to sort a multidomensional array by key name you cannot use array_multisort. ie: for an array named $archivos that prints like this:
Array
(
[0] => Array
(
[index] => 0
[name] => test
)
[1] => Array
(
[index] => 0
[name] => watertaxi.jpg
)
[2] => Array
(
[index] => 0
[name] => 2_0003.JPG
)
[3] => Array
(
[index] => 0
[name] => 24A_0025.JPG
)
[4] => Array
(
[index] => 1
[name] => _CIMG3501.JPG
)
)
If I wanted to order by "name" I'd use:
function comparar($a, $b) {
return strnatcasecmp($a["name"], $b["name"]);
}
usort($archivos, "comparar");
This function performs a case insensitive string comparison using a "natural order" algorithm (strnatcasecmp), resulting in:
Array
(
[0] => Array
(
[index] => 0
[name] => 2_0003.JPG
)
[1] => Array
(
[index] => 0
[name] => 24A_0025.JPG
)
[2] => Array
(
[index] => 0
[name] => test
)
[3] => Array
(
[index] => 0
[name] => watertaxi.jpg
)
[4] => Array
(
[index] => 1
[name] => _CIMG3501.JPG
)
)`
kat dot n0spam at audiogalaxy dot com
23-Aug-2001 10:25
`If you're having problems with array_multisort changing variables in global space when it is called inside a function and you're not passing in the function parameters by reference you can alleviate the problem by calling array_multisort with its parameters by reference.
array_multisort(&$a, SORT_DESC, &$b);
More details here in my bug report:
http://www.php.net/bugs.php?id=12936`
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