1  var baseSum = require('./_baseSum');
 2  
 3  /** Used as references for various `Number` constants. */
 4  var NAN = 0 / 0;
 5  
 6  /**
 7   * The base implementation of `_.mean` and `_.meanBy` without support for
 8   * iteratee shorthands.
 9   *
10   * @private
11   * @param {Array} array The array to iterate over.
12   * @param {Function} iteratee The function invoked per iteration.
13   * @returns {number} Returns the mean.
14   */
15  function baseMean(array, iteratee) {
16    var length = array == null ? 0 : array.length;
17    return length ? (baseSum(array, iteratee) / length) : NAN;
18  }
19  
20  module.exports = baseMean;