Plotting a ratio without plotting underlying data

[lampalork]

Dear All,

I have a custom indicator that just calculates the ratio between 2 data series (data0 / data1). See indicator code and initialization below. I would like to plot the ratio indicator without ploting the 2 underlying series (i deactivate plotting for these series using data0.plotinfo.plot = False)? When i deactivate any of these data series, the ratio indicator automatically disappears. I think it is because the master relationship with underlying data. What is the best way to work around this? Thanks!

class DivisionIndicator(bt.Indicator):

    _mindatas = 2  # requires two (2) data sources
    alias = ('DVD',)
    lines = ('div',)

    params = (
        ('not_required', 20),
    )

    plotlines = dict(
        divisor_ind=dict(
            _name='DVD',
            color='green',
            alpha=0.50
        )
    )

    def nextstart(self):
        self.l.div[0] = self.data0[0] / self.data1[0]  # seed value

    def next(self):
        d = self.data0[0] / self.data1[0]
        self.l.div[0] = d if d else self.l.div[-1]

    def oncestart(self, start, end):
        self.line.array[start] = (
            self.data0.array[start] - self.data1.array[start])

    def once(self, start, end):
        d0array = self.data0.array
        d1array = self.data1.array
        larray = self.line.array

        prev = larray[start - 1]
        for i in range(start, end):
            d = d0array[i] / d1array[i]
            larray[i] = prev = d if d else prev

class CalvadosStrategy(bt.Strategy):
      def __init__(self):
        my_ratio = DivisionIndicator(self.datas[1], self.datas[2])
        ...

[backtrader]

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