mathball/lib/median/index.js

A JavaScript library for Competitive Programming

'use strict';

/* Function: median() */

var validate = require('../validation/number-array');

module.exports = function (arr) {
  validate(arr, 'median');
  arr.sort(function (a, b) {
    return a - b;
  });

  var half = Math.floor(arr.length / 2);

  if (arr.length % 2) {
    return arr[half];
  } else {
    return (arr[half - 1] + arr[half]) / 2.0;
  }
};