//随机生成1万个元素的数组
for($i=0;$i<10000;$i++){
 $ary[]=rand(1,100000);
}
$ary=array_unique($ary); //去重复数值
sort($ary);//顺序排序
$min_10=array_slice($ary,0, 10);//取出最小的10个数值
$max_10=array_slice($ary,-10, 10);//取出最大的10个数值
rsort($max_10);//倒序排序最大的10个数值
echo '<pre>';
print_r($min_10);
print_r($max_10);
unset($ary,$min_10,$max_10);

Array
(
  [0] => 16
  [1] => 19
  [2] => 22
  [3] => 31
  [4] => 40
  [5] => 49
  [6] => 71
  [7] => 74
  [8] => 80
  [9] => 92
)
Array
(
  [0] => 99997
  [1] => 99991
  [2] => 99973
  [3] => 99958
  [4] => 99955
  [5] => 99946
  [6] => 99939
  [7] => 99933
  [8] => 99927
  [9] => 99900
)