/*! © SpryMedia Ltd - datatables.net/license */

import $ from 'jquery';
import DataTable from 'datatables.net';

/**
 * It can sometimes be useful to get the average of data in an API result set,
 * be it from a column, or a collection of cells. This method provides exactly
 * that ability.
 *
 * @name average()
 * @summary Average the values in a data set.
 * @author [Allan Jardine](http://sprymedia.co.uk)
 * @requires DataTables 1.10+
 *
 * @returns {Number} Calculated average
 *
 * @example
 *    // Average a column
 *    var table = $('#example').DataTable();
 *    table.column( 3 ).data().average();
 *
 * @example
 *    // Average two cells
 *    var table = $('#example').DataTable();
 *    table.cells( 0, [3,4] ).data().average();
 */
DataTable.Api.register('average()', function () {
    var data = this.flatten();
    var sum = data.reduce(function (a, b) {
        return a * 1 + b * 1; // cast values in-case they are strings
    }, 0);
    return sum / data.length;
});


export default DataTable;