Creating a unique array on some conditon PHP

Question

I have an associative array $result represented as

$result[0]['id']=120
$result[0]['point']=3.4
$result[1]['id']=136
$result[1]['point']=4.5
$result[2]['id']=140
$result[2]['point']=5.6
$result[3]['id']=120
$result[3]['point']=6.7

I want to make this array unique by id, but on a condition that the the unique array contains element with the higher point. For the above example I wanted the output to be

$result[0]['id']=136
$result[0]['point']=4.5
$result[1]['id']=140
$result[1]['point']=5.6
$result[2]['id']=120
$result[2]['point']=6.7

I tried the code below it will only make the array unique by id, but cannot check the condition.

function super_unique($array, $key) {
    $temp_array = array();
        foreach($array as & $v) {
            if (!isset($temp_array[$v[$key]]))
            $temp_array[$v[$key]] = & $v;
        }
    $array = array_values($temp_array);
    return $array;
}

Please help thanks in advance

score 0 · Answer 1 · answered Feb 26 '14 at 19:02

$newarr = array();
foreach($array as $v) {
    if (!isset($newarr[$v['id']]) || ($newarr[$v['id']] < $v['point'])) {
       $newarr[$v['id']] = $v['point'];
    }
}

General tip: Don't use references like you are in the foreach loop. While it's not a concern with this particular code snippet, referenced varaibles in foreach loops can cause very-hard-to-find bugs in code where that particular variable name is re-used later on in later code.

Should i use this in the above function – user3357227 Feb 26 '14 at 19:07 — user3357227, Feb 26 '14 at 19:07

score 0 · Answer 2 · answered Feb 26 '14 at 19:23

$test = super_unique($result);
var_dump($test);


function super_unique($array){
    $newArray = array();    
    foreach($array as $val){
        $id = $val["id"];
        $point = $val["point"];
        if(!isset($newArray["$id"]) || ($point > $newArray["$id"])){
            $newArray["$id"] = $point;
        }
    }
    //asort($newArray); want to sorting by point???
    $output = array();
    $i = 0;
    foreach($newArray as $key => $value){
        $output[$i]["id"] = $key;
        $output[$i]["point"]=$value;
        $i++;
    }
    return $output;
}

But this is not working ..what if I have one more element named $result['score'] for each array — user3357227, Feb 26 '14 at 19:44

Creating a unique array on some conditon PHP

2 Answers2