Calculate Total of one column

Hello, i use the footerCallBack to calculate the Total based in Points of Exchange, I have a table width products, each row have a checkbox to select and send to server. When I select any checkbox, I'd like to that total will be updated. Course, using the api of DataTables. Some Ideas?.
Thanks.

<code>
"footerCallback" : function() {
var total;
var pageTotal;
var oTable = this;
var api = oTable.api();
var data;

            // Remove the formatting to get integer data for summation
            var intVal = function(i) {
                return typeof i === 'string' ?
                    i.replace(/[\$,]/g, '') * 1 :
                    typeof i === 'number' ?
                        i : 0;
            };

            // Total over all pages
            data = api.column(7).data();
            total = data.length ?
                data.reduce(function(a, b) {
                    return intVal(a) + intVal(b);
                }) :
                0;

            // Total over this page
            data = api.column(7, { page: 'current' }).data();
            pageTotal = data.length ?
                data.reduce(function(a, b) {
                    return intVal(a) + intVal(b);
                }) :
                0;

            // Update footer
            $(api.column(7).footer()).html(
                'Puntos ' + pageTotal + ' ( Puntos ' + total + ' total)'
            );
        }

</code>