jquery: how to check if all radio buttons in a div are selected

Question

my html looks like this

Answer 1

Solution here http://jsfiddle.net/QxdnZ/1/

    var checked = $("#div1 :radio:checked");
    var groups = [];
    $("#div1 :radio").each(function() {
        if (groups.indexOf(this.name) < 0) {
            groups.push(this.name);
        }
    });
    if (groups.length == checked.length) {
        alert('all are checked!');
    }
    else {
        var total = groups.length - checked.length;
        var a = total>1?' groups are ':' group is ';

        alert(total + a + 'not selected');
    }