R/pmand.R

In piLaboratory/sads: Maximum Likelihood Models for Species Abundance Distributions

pmand <- function (q, N, s, v, lower.tail = TRUE, log.p = FALSE){
    N[ !is.finite(N) | N < 1 | !is.wholenumber(N) ] <- NaN
    s[ !is.finite(s) | s <= 0] <- NaN
    v[ !is.finite(v) | v < 0] <- NaN
    y <- c()
    for (i in 1:length(q)) {
        if (is.nan(q[i])) y[i] <- NaN
        else y[i] <- log(sum(1/((1:q[i])+v)^s)) - log(sum(1/((1:N)+v)^s))
    }
    y <- exp(y)
    if (any(!is.wholenumber(q))) warning("non integer values in q")
    y[ ! is.wholenumber(q) | q < 1 ] <- 0
    y[q > N] <- 1
    if (!lower.tail) y <- 1 - y
    if (log.p) y <- log(y)
    if (any(is.nan(y))) warning ("NaNs produced")
    return(y)
}