(self, interval)
return 1 - math.exp(-interval / self.period)
Calculate the alpha based on the time since the last tick. This is
        necessary because a single threaded Python program loses precision  
        under high load, so we can't assume a consistant I{EWMA._interval}.

        :type interval: C{float}
        :param interval: the interval we use to calculate the alpha
Calculate the alpha based on the time since the last tick. This is
        necessary because a single threaded Python program loses precision  
        under high load, so we can't assume a consistant I{EWMA._interval}.
Calculate the alpha based on the time since the last tick . This is necessary because a single threaded Python program loses precision under high load so we can t assume a consistant I { EWMA . _interval } .
def _alpha(self, interval):
        """
        Calculate the alpha based on the time since the last tick. This is
        necessary because a single threaded Python program loses precision  
        under high load, so we can't assume a consistant I{EWMA._interval}.

        :type interval: C{float}
        :param interval: the interval we use to calculate the alpha
        """
        return 1 - math.exp(-interval / self.period)
def _alpha ( self , interval ) : return 1 - math . exp ( - interval / self . period )