Calculates statistical cumulative distribution functions
(P-values their inverses, and parameters of the distributions).
Distributions include Incomplete Beta, Binomial, Negative Binomial,
Chi-square, Non-central Chi-square, F, Non-central F, Incomplete
Gamma, Normal, Poisson, and T. Program uses double precision library,
DCDFLIB. Packaging changed to allow entry of user's choice of
X or 1-X where appropriate and display of both. This allows calculations
of p-values quite near one and accurate cdf values that are also
close to 1.
(adapted from the documentation)