For information on converting to InterSystems IRIS,
see the InterSystems IRIS Adoption Guide
and the InterSystems IRIS In-Place Conversion Guide,
both available on the WRC Distributions page (login required).
An interface method for cumulative distribution function (CDF). Optionally provides a cumulative probability
of a value being between two values x1 and x2.
If called with 1 argument(x1) or if the value of second argument is empty string then
returns CDF value for x1. If called with two arguments, x1 and x2 then returns
a probability of a value being between x1 and x2.