这样的数组如何降序输出？

[kwwlysua]

$arr=array(array('132','20120524','23232.2','21.31'),array('126','20120524','-231232.2','13.321'),array('321','20120524','232.32','1.31')));

根据第3小组数据进行降序输出，请老师指教，谢谢！

[༺ཌༀཉི浮华背后༃ༀད༻]

$arr=array(array('132','20120524','23232.2','21.31'),array('126','20120524','-231232.2','13.321'),array('321','20120524','232.32','1.31'));
$tmp = array_multisort($arr,SORT_DESC,SORT_REGULAR);
print_r($arr);
#Array ( [0] => Array ( [0] => 321 [1] => 20120524 [2] => 232.32 [3] => 1.31 ) [1] => Array ( [0] => 132 [1] => 20120524 [2] => 23232.2 [3] => 21.31 ) [2] => Array ( [0] => 126 [1] => 20120524 [2] => -231232.2 [3] => 13.321 ) ) 

[一起混吧]

foreach($arr as $v) $t[]=$v[2];
array_multisort($t,SORT_DESC,$arr);
print_r($arr);

[qq120848369]

[Quote=引用 2 楼 的回复:]

PHP code
foreach($arr as $v) $t[]=$v[2];
array_multisort($t,SORT_DESC,$arr);
print_r($arr);
[/Quote]

++

[itcaicai]

什么叫“根据第3小组数据进行降序输出？”
你的二维数组数据格式
arr[0]'132','20120524','23232.2','21.31'
arr[1]'126','20120524','-231232.2','13.321'
arr[2]'321','20120524','232.32','1.31'
你想要把arr[2]降序后输出整个数组，还是根据最后一列的大小顺序排列arr[0]arr[1]and arr[2]?

[Quote=引用楼主 的回复:]
$arr=array(array('132','20120524','23232.2','21.31'),array('126','20120524','-231232.2','13.321'),array('321','20120524','232.32','1.31')));

根据第3小组数据进行降序输出，请老师指教，谢谢！
[/Quote]

[qq120848369]

<?php
$arr=array(array('132','20120524','23232.2','21.31'),array('126','20120524','-231232.2','13.321'),array('321','20120524','232.32','1.31'));
uasort($arr, function($left, $right) {
                        if ($left[2] < $right[2]) {
                                return -1;
                        } else if ($left[2] == $right[2]) {
                                return 0;
                        } else {
                                return 1;
                        }
                });
print_r($arr);
?>

了解了一下，multisort在key相等的时候会用接下来的字段做比较，这里不合适。