PHP loop with set intervals - php

Question

I have the following code that converts my twitter account rss feed into a string so that I can parse my followers user names.
$url = file_get_contents("MY_TWITTER_RSS_FEED_URL_GOES_HERE");
$source = simplexml_load_string($url);
foreach ($source as $match){
//name of node
$username = "&nbsp#".$match->author->name;
//removes the name and parentheses ex.kyrober555 (Robert)
$usernames = substr($username, 0, strpos($username, ' '));
//returns usernames only ex.kyrober555
echo $usernames;
}
Using the foreach loop I return all 15 names from the feed and it looks like this.
#ajay54 #marymary770 #funnigurl1209 #jimiwhitten #kyroberthl #tree_bear #crftyldy #sanbrt63 #Sandra516 #DreamFog #KravenSwagNBzz #DreamFog #TheCrippledDuck #TheCrippledDuck #Cass60
Now here is what I would like to do, but I am not sure if its possible, and I wouldn'y know how so I ask for your help. When I load the page for this php file it returns all user names at once. What I would like to do is return 5 user names then do something then return 5 more then do something else then return the last 5. Maybe something like this but I don't know...
foreach ($source as $match){
/* Return the 1st 5 user names */
/* do some other type of coding */
/* Return the second set of 5 usernames */
/* do something here */
/* return the last 5 usernames */
}
Ultimately returning all 15 user names, but at different intervals not all at once.

Answer 1

array_slice() is always nice. Something like this maybe:
for($offset = 0; $offset < count($array); $offset += 5){
$slice = array_slice($array, $offset, 5);
// Do your stuff
}

Answer 2

$count = 0;
foreach ($source as $match){
$username = "&nbsp#".$match->author->name;
$usernames = substr($username, 0, strpos($username, ' '));
echo $usernames;
if($count % 5 == 0 && $count > 0) {
// do something else;
}
$count++;
}
Thanks #vichle for you comment, maybe it's better to use a matrix then?
$count = 0;
$userArray = array();
foreach ($source as $match){
$username = "&nbsp#".$match->author->name;
$usernames = substr($username, 0, strpos($username, ' '));
$userArray[$count % 5][] = $usernames;
$count++;
}
This code will probably need tweaking, but it's a start.. Now you've got an array within an array. $userArray[0] will return an array with the first 5 usernames, $userArray[1] will return an array with the second 5 usernames, etc.