metrology/instruments/histogram.py
def variance(self):
        """Returns variance"""
        if self.counter.value <= 1:
            return 0.0
        return self.var.value[1] / (self.counter.value - 1)
def variance(self):
        """Returns variance"""
        if self.counter.value <= 1:
            return 0.0
        return self.var.value[1] / (self.counter.value - 1)
Returns variance