How to sum all column values in multi-dimensional array?

Question

How can I add all the columnar values by associative key? Note that key sets are dynamic.

Input array:

Arr         


        

Answer 1

Here you have how I usually do this kind of operations.

// We declare an empty array in wich we will store the results
$sumArray = array();

// We loop through all the key-value pairs in $myArray
foreach ($myArray as $k=>$subArray) {

   // Each value is an array, we loop through it
   foreach ($subArray as $id=>$value) {

       // If $sumArray has not $id as key we initialize it to zero  
       if(!isset($sumArray[$id])){
           $sumArray[$id] = 0;
       }

       // If the array already has a key named $id, we increment its value
       $sumArray[$id]+=$value;
    }
 }

 print_r($sumArray);