php join array with same initial value - php

Question

here's my array
Array
(
[0] => Array
(
[0] => Jan 2010
[1] => 65.75
)
[1] => Array
(
[0] => Jan 2010
[1] => 211.05
)
[2] => Array
(
[0] => Jan 2010
[1] => 582.7
)
[3] => Array
(
[0] => Feb 2010
[1] => 136.3
)
[4] => Array
(
[0] => Feb 2010
[1] => 215.32
)
[5] => Array
(
[0] => Feb 2010
[1] => 413.9
)
[6] => Array
(
[0] => Mar 2010
[1] => 156.35
)
[7] => Array
(
[0] => Mar 2010
[1] => 210.54
)
[8] => Array
(
[0] => Mar 2010
[1] => 585.15
)
[9] => Array
(
[0] => Apr 2010
[1] => 126.1
)
[10] => Array
(
[0] => Apr 2010
[1] => 255.47
)
[11] => Array
(
[0] => Apr 2010
[1] => 329.1
)
[12] => Array
(
[0] => May 2010
[1] => 109
)
[13] => Array
(
[0] => May 2010
[1] => 170
)
[14] => Array
(
[0] => May 2010
[1] => 716.7
)
)
is there any way I can make all arrays with the same value in [0] merge? i want it to be something like this:
Array[0] = (Jan 2010, 65.75, 211.05, 582.7)
Array[1] = (Feb 2010, 136.3, 215.32, 413.9)
and so on...

Answer 1

The closest I can think to do this "simply" (read: taking advantage of native PHP features) is switching to text keys (associative array) for your result. This makes sense from a data modeling perspective as well, since in your sample result arrays you are mixing "key" data and "value" data (e.g. the first value carries the responsibility of being the label for the set == bad). The trick is to use the implicit "push" operator [], which appends a new value to an array.
foreach($sourceArray as $currentSubArray) {
$resultArray[$currentSubArray[0]][] = $currentSubArray[1];
}
Your result will look like this:
Array (
'Jan 2010' => Array (
0 => 65.75,
1 => 211.05,
2 => 582.7,
)
...
)

Answer 2

This is a variant of what #ctrahey suggested, that operates on the input array directly:
foreach($array as $key => &$entry) {
list($month, $value) = $entry;
if (isset($ptr[$month])) {
$ptr[$month][] = $value;
unset($array[$key]);
} else {
$ptr[$month] = &$entry;
}
}
unset($ptr);
Output with your example data:
Array
(
[0] => Array
(
[0] => Jan 2010
[1] => 65.75
[2] => 211.05
[3] => 582.7
)
[3] => Array
(
[0] => Feb 2010
[1] => 136.3
[2] => 215.32
[3] => 413.9
)
[6] => Array
(
[0] => Mar 2010
[1] => 156.35
[2] => 210.54
[3] => 585.15
)
[9] => Array
(
[0] => Apr 2010
[1] => 126.1
[2] => 255.47
[3] => 329.1
)
[12] => Array
(
[0] => May 2010
[1] => 109
[2] => 170
[3] => 716.7
)
)

Answer 3

actionMerge($inputArray);
function actionMerge($inputArray){
$month = array();
$earn = array();
$parentKey = 0;
$callback = function ($value, $key) use (&$month, &$earn, &$parentKey) {
if(!is_array($value)){
if($key == 0){
if(!in_array($value, $month)){
array_push($month, $value);
$earn[$value] = array();
}
$parentKey = $value;
}elseif($key == 1){
array_push($earn[$parentKey], $value);
}
}
};
array_walk_recursive($inputArray, $callback);
echo 'You should use this array';
var_dump($earn); // group money by month, I recommend you to use it
$Array = array();
foreach($month as $m){
$arr = array($m);
$arr = array_merge($arr, $earn[$m]);
array_push($Array, $arr);
}
echo '...Intead of array result what you expect';
var_dump($Array); // your expect result
}
?>
Here is result:
//You should use this array
array (size=5)
'Jan 2010' =>
array (size=3)
0 => float 65.75
1 => float 211.05
2 => float 582.7
'Feb 2010' =>
array (size=3)
0 => float 136.3
1 => float 215.32
2 => float 413.9
'Mar 2010' =>
array (size=3)
0 => float 156.35
1 => float 210.54
2 => float 585.15
'Apr 2010' =>
array (size=3)
0 => float 126.1
1 => float 255.47
2 => float 329.1
'May 2010' =>
array (size=3)
0 => int 109
1 => int 170
2 => float 716.7
//...Intead of array result what you expect
array (size=5)
0 =>
array (size=4)
0 => string 'Jan 2010' (length=8)
1 => float 65.75
2 => float 211.05
3 => float 582.7
1 =>
array (size=4)
0 => string 'Feb 2010' (length=8)
1 => float 136.3
2 => float 215.32
3 => float 413.9
2 =>
array (size=4)
0 => string 'Mar 2010' (length=8)
1 => float 156.35
2 => float 210.54
3 => float 585.15
3 =>
array (size=4)
0 => string 'Apr 2010' (length=8)
1 => float 126.1
2 => float 255.47
3 => float 329.1
4 =>
array (size=4)
0 => string 'May 2010' (length=8)
1 => int 109
2 => int 170
3 => float 716.7

Answer 4

It's quite horrible,but it works...
$resarray=Array(
0 => Array(0 => 'Jan 2010',1 => 65.75),
1=> Array(0 => 'Jan 2010',1 => 211.05),
2 => Array(0 => 'Jan 2010',1 => 582.7),
3 => Array(0 => 'Feb 2010',1 => 136.3),
4 => Array(0 => 'Feb 2010',1 => 215.32),
5 => Array(0 => 'Feb 2010',1 => 413.9),
6 => Array(0 => 'Feb 2010',1 => 156.35),
7 => Array(0 => 'Feb 2010',1 => 210.54),
8 => Array(0 => 'Mar 2010',1 => 585.15),
9 => Array(0 => 'Apr 2010',1 => 126.1),
10 => Array(0 => 'Apr 2010',1 => 255.47),
11 => Array(0 => 'Apr 2010',1 => 329.1),
12 => Array(0 => 'May 2010',1 => 109),
13 => Array(0 => 'May 2010',1 => 170),
14 => Array(0 => 'May 2010',1 => 716.7)
);
$CatArray=array();
$FinArray=array();
$count=count($resarray);
for($i=0;$i<$count;$i++){
$index=array_search($resarray[$i][0],$CatArray);
if(is_numeric($index) && $index>=0)
$FinArray[$index][]=$resarray[$i][1];
else{
$CatArray[]=$resarray[$i][0];
$FinArray[]=array($resarray[$i][0],$resarray[$i][1]);
}
}
unset($CatArray);
unset($resarray);
$count=count($FinArray);
for($i=0;$i<$count;$i++){
$resarray[$i]=implode(',',$FinArray[$i]);
}
Output:
Array
(
[0] => Jan 2010,65.75,211.05,582.7
[1] => Feb 2010,136.3,215.32,413.9,156.35,210.54
[2] => Mar 2010,585.15
[3] => Apr 2010,126.1,255.47,329.1
[4] => May 2010,109,170,716.7
)