Consider you have two arrays like the below:

1) $arr1 = Array ( [0] => 2 [1] => 2 [2] => 2 [3] => 3 [4] => 3 ) 2) $arr2 = Array ( [0] => 28 [1] => 48 [2] => 21 [3] => 160 [4] => 10 )

You wants to make arr1 key for arr2, You can use phps standard array function i.e., array_combine like:

array_combine($arr1, $arr2);

It will result you:

array ( [2] => 21 [3] => 10 )

But some time you may need to combine the arrays that it always contains max value for a key for ex:

array ( [2] => 48 [3] => 160 )

Then you will be needed to write custom code:

Function Call: $newArray = getNewArray($arr1, $arr2);

Function Definition:

public function getNewArray($arr1, $arr2) { $arrayChunks = array(); $arrayMaxChunks = array();

 //Split the array into chunks based on similiar keys
 foreach ($arr1 as $key => $value) {
     if($key==0)
       $arrayChunks[$arr1[0]][] = $arr2[0];
    else
       $arrayChunks[$arr1[$key]][0] = $arr2[$key];  
 }

 // Find the maximum in each smaller array chunks
 foreach ($arrayChunks as $key => $value) {
     $arrayMaxChunks[$key] = max($value);
 }
 return $arrayMaxChunks;

}

It will result you: array ( [2] => 48 [3] => 160 )