pagination sphinx search

<?php
// Start Pagination

// number of rows to show per page
$rowsperpage = 10;
$numrows1 = $results[total];

// find out total pages
$totalpages = ceil($numrows1 / $rowsperpage);

// get the current page or set a default
if (isset($_GET['currentpage']) && is_numeric($_GET['currentpage'])) {
      // cast var as int
      $currentpage = (int) $_GET['currentpage'];
      } else {
      // default page num
      $currentpage = 1;
} // end if

// if current page is greater than total pages...
if ($currentpage > $totalpages) {
      // set current page to last page
      $currentpage = $totalpages;
} // end if

// if current page is less than first page...
if ($currentpage < 1) {
      // set current page to first page
      $currentpage = 1;
} // end if

// the offset of the list, based on current page
$offset = (($currentpage - 1) * $rowsperpage);

$sphinx->SetLimits($offset, $rowsperpage);

echo "<b>Found $results[total_found] Matches</b><br>\n";

$showingto = ($offset + $rowsperpage > $numrows1) ? $numrows1 : $offset + $rowsperpage;
echo "Showing results " . ($offset+1) . " - " . $showingto . " of " . $numrows1;

?>