Indicator NaN in Strategy class but not in Indicator class

[LeggoMaEggo]

I am missing something such that the indicator line isn't being read properly in the strategy, but is read properly in the indicator itself?

class SlopeCalc(bt.Indicator):
    lines = ('slopescalcs',)
    params = dict(typeToCalc='volatility', period=5)

    def __init__(self):
        if self.params.typeToCalc == 'volatility':
            self.lines.slopecalc = bt.talib.VAR(self.data.close, timeperiod=self.params.period, nbdev=1.0)
    
    def next(self):
        print("in ind", self.lines.slopecalc[0])

class LaneStrategy(bt.Strategy):

    def log(self, txt, dt=None):
        ''' Logging function for this strategy'''
        dt = dt or self.datas[0].datetime.date(0)
        print('%s, %s' % (dt.isoformat(), txt))

    def __init__(self):
        # Keep a reference to the "close" line in the data[0] dataseries
        self.dataclose = self.datas[0].close

        self.slopevolat = SlopeCalc()


    def next(self):
        print("in strat",self.slopevolat[0])

Printing yields:

in ind 6.162160000044992e-07
in strat nan
in ind 5.590959997192613e-07
in strat nan
in ind 3.006904000013577e-06
in strat nan
in ind 8.901303999886423e-06
in strat nan
in ind 1.0513023999569882e-05
in strat nan
in ind 6.540775999708259e-06
in strat nan
in ind 4.6533039999019365e-06
in strat nan
in ind 1.3609624000210374e-05
in strat nan
in ind 2.923282400013605e-05
in strat nan
in ind 2.4948944000069417e-05
in strat nan
in ind 1.0268935999757645e-05
.....

[run-out]

@leggomaeggo said in Indicator NaN in Strategy class but not in Indicator class:

lines = ('slopescalcs',)

Missing an s

if self.params.typeToCalc == 'volatility':
            self.lines.slopecalc = bt.talib.VAR(self.data.close, timeperiod=self.params.period, nbdev=1.0)