'Add autoscaling minor ticks to the axes.'

def minorticks_on(self):

    for ax in (self.xaxis, self.yaxis):
        scale = ax.get_scale()
        if (scale == u'log'):
            s = ax._scale
            ax.set_minor_locator(mticker.LogLocator(s.base, s.subs))
        elif (scale == u'symlog'):
            s = ax._scale
            ax.set_minor_locator(mticker.SymmetricalLogLocator(s._transform, s.subs))
        else:
            ax.set_minor_locator(mticker.AutoMinorLocator())
