Convert mean and standard deviation into log-normal distribution parameters

Source: R/bayes_functions.R

lnHyperPars is a function for calculating parameters for a log-normal distribution, such that the distribution yields desired mean and standard deviation. Used for sampling the a-parameter.

lnHyperPars(mean, sd)

Arguments

mean

the desired mean.

sd

the desired standard deviation.

Value

lnHyperPars returns two values. These can be directly supplied to rlnorm.

Examples

pars <- lnHyperPars(2, 4)
x <- rlnorm(1000000, pars[1], pars[2])
mean(x) # close to 2
#> [1] 2.001359
sd(x)   # close to 4
#> [1] 4.007878