Display "time ago" instead of datetime in PHP Codeigniter
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I would like to display a time format like twitter and FB (Posted 3 hours ago, Posted 2 minutes ago and so on...)

I've tried this piece of code without success : 

    function format_interval($timestamp, $granularity = 2) {
      $units = array('1 year|@count years' => 31536000, '1 week|@count weeks' => 604800, '1 day|@count days' => 86400, '1 hour|@count hours' => 3600, '1 min|@count min' => 60, '1 sec|@count sec' => 1);
      $output = '';
      foreach ($units as $key => $value) {
        $key = explode('|', $key);
        if ($timestamp >= $value) {
          $floor = floor($timestamp / $value);
          $output .= ($output ? ' ' : '') . ($floor == 1 ? $key[0] : str_replace('@count', $floor, $key[1]));
          $timestamp %= $value;
          $granularity--;
        }
    
        if ($granularity == 0) {
          break;
        }
    }

I use this function with a callback into another function like : $this->format_interval(); and pass it to my View

My current format date is : **2012-07-26 09:31:pm** and already stored in my DB

Any help will be very appreciated!