For the default values of scale
and min
(see below), the density function for an exponential distribution is . This means that random values that come from such an exponential distribution are concentrated in the smaller values.
The exponential functions described below take two optional parameters, scale
, which defaults to 1, and min
, which defaults to 0. The standard deviation of exponentially distributed numbers equals the scale, and the mean equals the sum of the minimum and the scale. We let E represent a random variable having an exponential distribution.
A plot of both an exponential density and its cumulative probability.
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