note 70402 deleted from function.rand by felipe

Note Submitter: php at ngaru dot com 

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Here is a function that selects a random bunch of rows from a database statement.  The getdata() function returns a multidimensional array of data (e.g. - just to explain - dont take this literally)
$data[0] = array("ID"=>1, "name", "test row 1");
$data[1] = array("ID"=>2, "name", "test row 2");

function randomselection($sql, $c, $withoutreplacement = 1) {
 //$c = count of rows to be selected
 $data = getdata($sql);
 $totalcount = count($data);
 $j = array();
 if($totalcount < $c) {//not enough data points
  return $data;
 }
 for($i = 0; $i < $c; $i++) {
  $exists = 1
  if($withoutreplacement) {
   while($exists > 0 && $exists < 100) {
    $j[$i] = floor(rand(0,$totalcount-1));
    if(!in_array( $j[$i] , $j , 1 )) {
     $exists = 0;
    }
    else {
     $exists++;
    }
   }
  }
  else {
   $j[$i] = floor(rand(0,$totalcount-1));
  }
  $newdata[$i] = $data[$j[$i]];
 }
 return $newdata;
}