def tick(self, index, length):
        """
        Add tick marks in order of axes by width
        APIPARAM: chxtc     <axis index>,<length of tick mark>
        """
        assert int(length) <= 25, 'Width cannot be more than 25'
        self.data['ticks'].append('%s,%d'%(index,length))
        return self.parent
Add tick marks in order of axes by width
        APIPARAM: chxtc     <axis index>,<length of tick mark>