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Drupal Call views with different row options

// Contest listing
$view_modes = array('grid', 'teaser');

foreach ($view_modes as $view_mode) {
  $view    = &${'contest_'.$view_mode};
  $display = &${'display_contest_'.$view_mode};

  $view    = views_get_view('contest_listings');
  $display = $view->display[$sort];
  $display->display_options['row_options']['view_mode'] = $view_mode;

  $listing[$view_mode]   = $view->preview($sort, array($tid));
}