Description Density, distribution function, quantile function and random generation for the truncated Normal distribution with mean equal to mean and standard deviation equal to sd before truncation, and truncated on the interval [lower, upper]. Usage dtnorm(x, mean=0, sd=1, lower=-Inf, upper=Inf, log = FALSE) ptnorm(q, mean=0, sd=1, lower=-Inf, upper=Inf, lower.tail = TRUE, log.p = FALSE) qtnorm(