Largest negative number in array

largest-neg-num-in-array.js

/**
 * returns the largest negative number in a given array
 * @param  {Array} arr     [the array to act on]
 * @return {Number}        [the largest negative number]
 */
function getLargestNegNumInArr(arr) {
  return arr.reduce(function(prevVal, curVal) {
    if (curVal < prevVal) {
      prevVal = curVal;
    }
    return prevVal;
  }, 0);
}