php二维数组怎么求和

导语：数组是php语言的'一大难题。以下的是本站小编为大家搜集的php基二维数组求和的方法，希望对你有所帮助。

　　数组：

$a = array(array("a"=>"aa","a1"=>1,"a2"=>1),array("a"=>"bb","a1"=>2,"a2"=>2),array("a"=>"cc","a1"=>3,"a2"=>3),

array("a"=>"aa","a1"=>1,"a2"=>1),array("a"=>"bb","a1"=>5,"a2"=>5))

　　第一个键值相同的元素 求和

　　结果

$r = array(array("a"=>"aa","a1"=>2,"a2"=>2),array("a"=>"bb","a1"=>7,"a2"=>7),array("a"=>"cc","a1"=>3,"a2"=>3));

------解决方案--------------------

$a = array(

array("a" => "aa", "a1" => 1, "a2" => 1),

array("a" => "bb", "a1" => 2, "a2" => 2),

array("a" => "cc", "a1" => 3, "a2" => 3),

array("a" => "aa", "a1" => 1, "a2" => 1),

array("a" => "bb", "a1" => 5, "a2" => 5),

);

$res = array();

foreach($a as $r) {

if(! isset($res[$r['a']])) $res[$r['a']] = $r;

else {

$res[$r['a']]['a1'] += $r['a1'];

$res[$r['a']]['a2'] += $r['a2'];

}

}

print_r(array_values($res));

Array

(

[0] => Array

(

[a] => aa

[a1] => 2

[a2] => 2

)

[1] => Array

(

[a] => bb

[a1] => 7

[a2] => 7

)

[2] => Array

(

[a] => cc

[a1] => 3

[a2] => 3

)

)