1 var baseIteratee = require('./_baseIteratee'),
2 baseSum = require('./_baseSum');
5 * This method is like `_.sum` except that it accepts `iteratee` which is
6 * invoked for each element in `array` to generate the value to be summed.
7 * The iteratee is invoked with one argument: (value).
12 * @param {Array} array The array to iterate over.
13 * @param {Function|Object|string} [iteratee=_.identity] The iteratee invoked per element.
14 * @returns {number} Returns the sum.
17 * var objects = [{ 'n': 4 }, { 'n': 2 }, { 'n': 8 }, { 'n': 6 }];
19 * _.sumBy(objects, function(o) { return o.n; });
22 * // The `_.property` iteratee shorthand.
23 * _.sumBy(objects, 'n');
26 function sumBy(array, iteratee) {
27 return (array && array.length)
28 ? baseSum(array, baseIteratee(iteratee))
32 module.exports = sumBy;