phpjs/_octopress/source/functions/max/index.markdown

php.js offers community built php functions in javascript

---
layout: page
title: "JavaScript max function"
comments: true
sharing: true
footer: true
alias:
- /functions/view/max:468
- /functions/view/max
- /functions/view/468
- /functions/max:468
- /functions/468
---
<!-- Generated by Rakefile:build -->
A JavaScript equivalent of PHP's max

{% codeblock math/max.js lang:js https://raw.github.com/kvz/phpjs/master/functions/math/max.js raw on github %}
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;
}
{% endcodeblock %}

 - [Raw function on GitHub](https://github.com/kvz/phpjs/blob/master/functions/math/max.js)

Please note that php.js uses JavaScript objects as substitutes for PHP arrays, they are 
the closest match to this hashtable-like data structure. 

Please also note that php.js offers community built functions and goes by the 
[McDonald's Theory](https://medium.com/what-i-learned-building/9216e1c9da7d). We'll put online 
functions that are far from perfect, in the hopes to spark better contributions. 
Do you have one? Then please just: 

 - [Edit on GitHub](https://github.com/kvz/phpjs/edit/master/functions/math/max.js)

### Example 1
This code
{% codeblock lang:js example %}
max(1, 3, 5, 6, 7);
{% endcodeblock %}

Should return
{% codeblock lang:js returns %}
7
{% endcodeblock %}

### Example 2
This code
{% codeblock lang:js example %}
max([2, 4, 5]);
{% endcodeblock %}

Should return
{% codeblock lang:js returns %}
5
{% endcodeblock %}

### Example 3
This code
{% codeblock lang:js example %}
max(0, 'hello');
{% endcodeblock %}

Should return
{% codeblock lang:js returns %}
0
{% endcodeblock %}


### Other PHP functions in the math extension
{% render_partial _includes/custom/math.html %}