Grouping Algorithm for Getting Started with PHP5

Example, split a set of data into 6 sets of output algorithms. Code:

$groupCount = 6; //Number of groups
$userIdList = array(1, 2, 3, 4, 5, 6, 7, 8, 9,10);
$size = count($userIdList );
$sizeGroupPer = floor($size / $groupCount );//The number of allocated items in each group
$criticalValue = $size % $groupCount; //Critical value
$startIndex = 0;
 $endIndex = 0;
for ($i = 0; $i < $groupCount ; $i++ ) {
 if ($i < $critical) { //Indicates which groups can be allocated more
 $endIndex = $startIndex + $sizeGroupPer + 1;
 } else {
 $endIndex = $startIndex + $sizeGroupPer ;
 } // bbs.it-home.org

$strGroup = "";
for ($j = $startIndex ; $j < $endIndex; $j++) {
 if (($j + 1) == $to) {
 $strGroup .= $arryData[$j];
 } else {
 $strGroup .= $arryData[$j ].",";
 }
 }
 $startIndex = $endIndex;
 echo "The ".$i." group data: ".$strGroup;
}