HTML Table Filter with jQuery

function filter_by_project(){
            var input, filter, table, tr, td, i;
            input = $("#project_filter").val();
            filter = input.toUpperCase();
            table = document.getElementById("receivings_table");
            tr = table.getElementsByTagName("tr");

            for (i = 0; i < tr.length; i++) {
                td = tr[i].getElementsByTagName("td")[3];
                if (td) {
                    if (td.innerHTML.toUpperCase().indexOf(filter) > -1) {
                        tr[i].style.display = "";
                    } else {
                        tr[i].style.display = "none";
                    }
                }
            }
        }