# Distribution â€‹

Values for variables in ADOxx are assigned using **Random Generator** objects. The kind of value assignment can vary; for instance this could be done via distributions. The following distribution types are possible:

**Continuous distribution functions:**exponential, uniform, and normal distribution; for variables of the type*Double*.**Discrete distribution:**for variables of the type*Enumeration*.

**Syntax of the continuous distribution functions:**

for

**normal distribution**: normal (<number1>;<number2>) Enter the expected value and the standard deviation for the normal distribution, where <number1> represents the expected value and <number2> stands for the standard deviation.**Example:**Normal(1200;100)The variable has a normal distribution with an expected value of 1200 and a standard deviation of 100.For

**exponential distribution**: exponential (<number>) Enter the expected value of the exponential distribution, letting <number> be 1 divided by the expected value.**Example:**Exponential(0,002)The variable has an exponential distribution with an expected value of 500.For

**uniform distribution**: uniform (<number1>;<number2>) Enter the boundaries for the uniform distribution, where <number1> indicates the lower boundary and <number2> the upper boundary.**Example:**Uniform(0;100)The variable is uniformly distributed between the boundaries 0 and 100.

**Syntax of the discrete distribution:**

Discrete (<Symbol1> <number1>;<Symbol2> <number2>; ...)

You can define two or more symbols with their corresponding probabilities (number1, number2,...). The sum of the probabilities must always equal one!

Attention

The entry of symbol names is case-sensitive. The symbol names shall not **start** with **numerals from 0 to 9**, **blanks** or **returns** and the **figures : ( ) . , ; '**. Also **blanks** and **returns**, as well as the **figures: ( ) . , ; '** arenot authorised in symbol names.

**Examples:**

**Discrete (YES 0.6;NO 0.4):**

The variable is assigned with a probability of 0.6 of being 'YES' and a probability of 0.4 of being 'NO'. Therefore two transition conditions <variable name>='YES' and <variable name>='NO' are valid and possible.

**Discrete (a 0.5;b 0.3;c 0.1;d 0.1):**

The variable is assigned with a probability of 0.5 of taking the value 'a', a probability of 0.3 of being 'b', a probability of 0.1 of taking the value 'c' and a probability of 0.1 of taking the value 'd'. The four possible transition conditions therefore are: <variable name>='a', <variable name>='b', <variable name>='c' and <variable name>='d'.