phpjs/functions/math/max.js

php.js offers community built php functions in javascript

function max() {
  // From: http://phpjs.org/functions
  // +   original by: Onno Marsman
  // +    revised by: Onno Marsman
  // +    tweaked by: Jack
  // %          note: Long code cause we're aiming for maximum PHP compatibility
  // *     example 1: max(1, 3, 5, 6, 7);
  // *     returns 1: 7
  // *     example 2: max([2, 4, 5]);
  // *     returns 2: 5
  // *     example 3: max(0, 'hello');
  // *     returns 3: 0
  // *     example 4: max('hello', 0);
  // *     returns 4: 'hello'
  // *     example 5: max(-1, 'hello');
  // *     returns 5: 'hello'
  // *     example 6: max([2, 4, 8], [2, 5, 7]);
  // *     returns 6: [2, 5, 7]
  var ar, retVal, i = 0,
      n = 0,
      argv = arguments,
      argc = argv.length,
      _obj2Array = function(obj) {
        if (Object.prototype.toString.call(obj) === '[object Array]') {
          return obj;
        }
        else {
          var ar = [];
          for (var i in obj) {
            if (obj.hasOwnProperty(i)) {
              ar.push(obj[i]);
            }
          }
          return ar;
        }
      }; //function _obj2Array
  _compare = function(current, next) {
    var i = 0,
            n = 0,
            tmp = 0,
            nl = 0,
            cl = 0;

    if (current === next) {
      return 0;
    }
    else if (typeof current === 'object') {
      if (typeof next === 'object') {
        current = _obj2Array(current);
        next = _obj2Array(next);
        cl = current.length;
        nl = next.length;
        if (nl > cl) {
          return 1;
        }
        else if (nl < cl) {
          return -1;
        }
        for (i = 0, n = cl; i < n; ++i) {
          tmp = _compare(current[i], next[i]);
          if (tmp == 1) {
            return 1;
          }
          else if (tmp == -1) {
            return -1;
          }
        }
        return 0;
      }
      return -1;
    }
    else if (typeof next === 'object') {
      return 1;
    }
    else if (isNaN(next) && !isNaN(current)) {
      if (current == 0) {
        return 0;
      }
      return (current < 0 ? 1 : -1);
    }
    else if (isNaN(current) && !isNaN(next)) {
      if (next == 0) {
        return 0;
      }
      return (next > 0 ? 1 : -1);
    }

    if (next == current) {
      return 0;
    }
    return (next > current ? 1 : -1);
  }; //function _compare
  if (argc === 0) {
    throw new Error('At least one value should be passed to max()');
  }
  else if (argc === 1) {
    if (typeof argv[0] === 'object') {
      ar = _obj2Array(argv[0]);
    }
    else {
      throw new Error('Wrong parameter count for max()');
    }
    if (ar.length === 0) {
      throw new Error('Array must contain at least one element for max()');
    }
  }
  else {
    ar = argv;
  }

  retVal = ar[0];
  for (i = 1, n = ar.length; i < n; ++i) {
    if (_compare(retVal, ar[i]) == 1) {
      retVal = ar[i];
    }
  }

  return retVal;
}