从二维数组中取出最小3个元素

/**
 * 从一个二维数组中取出 distance 最小的3个元素
 */

// 原数组
$arr = array(
    array(
        "id" => 1,
        "distance" => 256
    ),
    array(
        "id" => 2,
        "distance" => 546
    ),
    array(
        "id" => 3,
        "distance" => 128
    ),
    array(
        "id" => 4,
        "distance" => 56
    ),
    array(
        "id" => 5,
        "distance" => 356
    ),
    array(
        "id" => 6,
        "distance" => 466
    ),
    array(
        "id" => 7,
        "distance" => 796
    ),
    array(
        "id" => 8,
        "distance" => 664
    )
);

// 装入临时数组
$cur = array();
foreach ($arr as $key => $value) {
    $cur[$value['id']] = $value['distance'];
}
// 临时数组排序
sort($cur);

// 原数组排序、取值
$result = array();
foreach ($arr as $key => $value) {
    switch ($value['distance']) {
        case $cur[0]:
            $result[0] = $value;
            break;
        case $cur[1]:
            $result[1] = $value;
            break;
        case $cur[2]:
            $result[2] = $value;
            break;
    }
}
$arr = $result;
ksort($arr);

echo "

"; 
  
 var_export($arr); 
  
 echo "

";