Question

Say I have an a array like this:

Array (
  [0] => "bananas, apples, pineaples"
  [1] => "bananas, show cones"
  [2] => ""
  [3] => "apples, santa clause"
..
)

From that array I want to create a new array, holding each “tag”, and the number of times it occuredd in the first array, preferebly sorted alphabetically,like this:

Array (
  [apples] => 2
  [bananas] => 2
..
)

or

array (
  [0] => [apples] => 2
..
)

Answer 1

// array to hold the results
$start = array( "bananas, apples, pineaples", "bananas, show cones", "", "apples, santa clause" );
// array to hold the results
$result = array();

// loop through each of the array of strings with comma separated values
foreach ($start as $words){

    // create a new array of individual words by spitting on the commas
    $wordarray = explode(",", $words);
    foreach($wordarray as $word){
        // remove surrounding spaces
        $word = trim($word);
        // ignore blank entries
        if (empty($word)) continue;

        // check if this word is already in the results array
        if (isset($result[$word])){
            // if there is already an entry, increment the word count
            $result[$word] += 1;
        } else {
            // set the initial count to 1
            $result[$word] = 1;
        }
    }
}
// print results
print_r($result);