lib/stats.js
function(fn) {
			var arr = this.arr;

			if (arr.length === undefined) {
				// The wrapped array is a JSON object
				for (var key in arr) {
					this.arr[key] = fn.call(arr[key], arr[key], key, arr);
				}
			} else {
				// The wrapped array is an array
				for (var i = 0, l = this.arr.length; i < l; i++) {
					this.arr[i] = fn.call(arr[i], arr[i], i, arr);
				}
			}

			return this;
		}
function(fn) {
			var arr = this.arr;

			if (arr.length === undefined) {
				// The wrapped array is a JSON object
				for (var key in arr) {
					this.arr[key] = fn.call(arr[key], arr[key], key, arr);
				}
			} else {
				// The wrapped array is an array
				for (var i = 0, l = this.arr.length; i < l; i++) {
					this.arr[i] = fn.call(arr[i], arr[i], i, arr);
				}
			}

			return this;
		}
function ( fn ) { var arr = this . arr ; if ( arr . length === undefined ) { // The wrapped array is a JSON object
 for ( var key in arr ) { this . arr [ key ] = fn . call ( arr [ key ] , arr [ key ] , key , arr ) ; } } else { // The wrapped array is an array
 for ( var i = 0 , l = this . arr . length ; i < l ; i ++ ) { this . arr [ i ] = fn . call ( arr [ i ] , arr [ i ] , i , arr ) ; } } return this ; }
Replaces each element in an array or JSON object with the result of the function that is called against each element.  fn - The function to call on each element el    - The array or object element index - The index or key of the array element  Returns nothing.
Replaces each element in an array or JSON object with the result of the function that is called against each element . fn - The function to call on each element el - The array or object element index - The index or key of the array element Returns nothing .