Log Normal Distribution

Functions > Statistics > Probability Distributions > Log Normal Distribution

Log Normal Distribution

The following functions are associated with the log normal equation:

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• dlnorm(x, μ, σ)—Returns the probability density for value x.

• plnorm(x, μ, σ)—Returns the cumulative probability distribution for value x.

• qlnorm(p, μ, σ)—Returns the inverse cumulative probability distribution for probability p.

• rlnorm(m, μ, σ)—Returns a vector of m random numbers having the log normal distribution.

Arguments

x is a scalar or vector of real values, x ≥ 0. To allow integration and other operations over this argument, values outside of the stated range are allowed, but they produce a 0 result.

• μ is a real mean of the natural logs of x.

• σ is a real standard deviation of the natural logs of x, σ> 0.

• p is a real probability, 0 ≤ p ≤ 1.

• m is an integer, m > 0.