getProbability
public double getProbability(double x)
What is expected of this function is that it returns probability values with
the following conditions.
For x < = 0 you should return probability = 0. For x > = 1 should
return probability = 1. For values between [0,1] you must return values
between [0,1] according to the curve implemented.
This must be a monotonically increasing function. The reason is that a
growing form allows good behavior with high and low throughput.
Keep in mind that x represents how old the key is for which the probability
that it is expired is being requested. We will indicate x = 0 when the age of
the key is zero. X = 1 will be indicated when the ttl of the key has been
fulfilled.
- Parameters:
x - how old is the key in a normalized way age/ttl- Returns:
- a probability in the range of [0,1]