pgfIpoissonlindley: Function pgfIpoissonlindley
In Compounding: Computing Continuous Distributions

Description Usage Arguments Author(s) References Examples

This function calculates value of the pgf's inverse derivative of the Poisson-Lindley distribution.

1	pgfIpoissonlindley(s, params)

`s`	Value of the parameter of the pgf. It should be from interval [-1,1]. In the opposite pgf diverges.
`params`	Positive parameter of the Poisson-Lindley distribution, such that params<-theta.

S. Nadarajah, B. V. Popovic, M. M. Ristic

Johnson N, Kotz S, Kemp A (1992) Univariate Discrete Distributions, John Wiley and Sons, New York

http://www.am.qub.ac.uk/users/g.gribakin/sor/Chap3.pdf

params<-5
pgfIpoissonlindley(.9,params)


## The function is currently defined as

pgfIpoissonlindley <- function(s,params) {
    xval<-length(s)
    theta<-params[1]
    for (i in 1:length(s)) {
        func<-function(x) pgfpoissonlindley(x,params)-s[i]
        xval[i]<-uniroot(func,lower=0,upper=1)$root
    }
    xval
}