Gets value and uses it in a Select Option as default

getselectoption.js

<script>
	function getval(sel) {
       		$('#stars').val(sel.value);
    	}


	$(document).ready(function() {
		var valorestrella = $('#stars').val()-1;
		$('#starsrating option:eq('+valorestrella+')').prop('selected', true);
		$(".center_box_content").css("background-color","#47494c");
		$(".mgrid_table .highlight_light:odd").css("background-color","#f6f6f6");
	});
</script>