add to array if it isn't there already

Question

How do I add elements to an array only if they aren\'t in there already? I have the following:

$a=array();
// organize the array
foreach($array as $k=>$v)         


        

Answer 1

You'd have to check each value against in_array:

$a=array();
// organize the array by cusip
foreach($array as $k=>$v){
    foreach($v as $key=>$value){
        if(!in_array($value, $a)){
        $a[]=$value;
        }
    }
}