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Random Number Functions

Uniform Distribution​

Generates a random number between two values. Defaults to 0 and 1:
Syntax:     Rand(Min, Max)

Example:   Rand() → random number between 0 and 1
            Rand(5, 15)

Normal Distribution​

Returns a normally distributed value with a specified mean and standard deviation (defaults: 0 and 1):
Syntax:     RandNormal(Mean, StdDev)

Example:   RandNormal()
            RandNormal(100, 15)

Lognormal Distribution​

Generates a random number following a lognormal distribution:
Syntax:     RandLognormal(Mean, StdDev)

Example:   RandLognormal(0, 0.5)
            RandLognormal(1, 0.25)

Binary Distribution​

Returns 'true' with the given probability, otherwise 'false'. Default is 0.5:
Syntax:     RandBoolean(Probability)

Example:   RandBoolean() → fair coin flip
            RandBoolean(0.8)

Binomial Distribution​

Returns the number of successes from a fixed number of trials with a fixed success probability:
Syntax:     RandBinomial(Count, Probability)

Example:   RandBinomial(10, 0.5)
            RandBinomial(20, 0.3)

Negative Binomial Distribution​

Returns the number of trials required to achieve a specific number of successes:
Syntax:     RandNegativeBinomial(Successes, Probability)

Example:   RandNegativeBinomial(5, 0.25)
            RandNegativeBinomial(3, 0.5)

Poisson Distribution​

Simulates how often an event occurs within a specific time period:
Syntax:     RandPoisson(Lambda)

Example:   RandPoisson(5)
            RandPoisson(10)

Triangular Distribution​

Returns a value between a minimum and a maximum, with a most likely (peak) value:
Syntax:     RandTriangular(Min, Max, Peak)

Example:   RandTriangular(0, 10, 5)
            RandTriangular(1, 100, 30)

Exponential Distribution​

Models the time between independent events that occur at a constant rate:
Syntax:     RandExp(Lambda)

Example:   RandExp(1)
            RandExp(0.5)

Gamma Distribution​

Generates a random number with a gamma distribution based on shape (alpha) and rate (beta):
Syntax:     RandGamma(Alpha, Beta)

Example:   RandGamma(2, 2)
            RandGamma(1, 0.5)

Beta Distribution​

Generates a random number with a beta distribution using two shape parameters:
Syntax:     RandBeta(Alpha, Beta)

Example:   RandBeta(2, 5)
            RandBeta(1, 1)

Custom Distribution​

Generates a number from a custom distribution using x-values and their probabilities:
Syntax:     RandDist(X, Y)

Example:   RandDist({1, 2, 3}, {0.2, 0.5, 0.3})
            RandDist({-1, 0, 1}, {0.25, 0.5, 0.25})

SetRandSeed​

Fixes the seed of the random number generator for reproducible results:
Syntax:     SetRandSeed(Seed)

Example:   SetRandSeed(123)
            SetRandSeed(83940)