code: function(path)
  	{
  		if (path != null)
  		{
  			var index = path.lastIndexOf(mxCellPath.PATH_SEPARATOR);
  
  			if (index >= 0)
  			{
  				return path.substring(0, index);
  			}
  			else if (path.length > 0)
  			{
  				return '';
  			}
  		}
  
  		return null;
  	}
docs: Function: getParentPath
  
  Returns the path for the parent of the cell represented by the given
  path. Returns null if the given path has no parent.
  
  Parameters:
  
  path - Path whose parent path should be returned.