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simulation::random(n) 0.4 tcllib "Tcl Simulation Tools"

Name

simulation::random - Pseudo-random number generators

Table Of Contents

Synopsis

Description

This package consists of commands to generate pseudo-random number generators. These new commands deliver

For example:

    set p [::simulation::random::prng_Normal -1.0 10.0]

produces a new command (whose name is stored in the variable "p") that generates normally distributed numbers with a mean of -1.0 and a standard deviation of 10.0.

PROCEDURES

The package defines the following public procedures for discrete distributions:

::simulation::random::prng_Bernoulli p

Create a command (PRNG) that generates numbers with a Bernoulli distribution: the value is either 1 or 0, with a chance p to be 1

float p

Chance the outcome is 1

::simulation::random::prng_Discrete n

Create a command (PRNG) that generates numbers 0 to n-1 with equal probability.

int n

Number of different values (ranging from 0 to n-1)

::simulation::random::prng_Poisson lambda

Create a command (PRNG) that generates numbers according to the Poisson distribution.

float lambda

Mean number per time interval

The package defines the following public procedures for continuous distributions:

::simulation::random::prng_Uniform min max

Create a command (PRNG) that generates uniformly distributed numbers between "min" and "max".

float min

Minimum number that will be generated

float max

Maximum number that will be generated

::simulation::random::prng_Triangular min max

Create a command (PRNG) that generates triangularly distributed numbers between "min" and "max". If the argument min is lower than the argument max, then smaller values have higher probability and vice versa. In the first case the probability density function is of the form f(x) = 2(1-x) and the other case it is of the form f(x) = 2x.

float min

Minimum number that will be generated

float max

Maximum number that will be generated

::simulation::random::prng_SymmTriangular min max

Create a command (PRNG) that generates numbers distributed according to a symmetric triangle around the mean of "min" and "max".

float min

Minimum number that will be generated

float max

Maximum number that will be generated

::simulation::random::prng_Exponential min mean

Create a command (PRNG) that generates exponentially distributed numbers with a given minimum value and a given mean value.

float min

Minimum number that will be generated

float mean

Mean value for the numbers

::simulation::random::prng_Normal mean stdev

Create a command (PRNG) that generates normally distributed numbers with a given mean value and a given standard deviation.

float mean

Mean value for the numbers

float stdev

Standard deviation

::simulation::random::prng_Pareto min steep

Create a command (PRNG) that generates numbers distributed according to Pareto with a given minimum value and a given distribution steepness.

float min

Minimum number that will be generated

float steep

Steepness of the distribution

::simulation::random::prng_Gumbel min f

Create a command (PRNG) that generates numbers distributed according to Gumbel with a given minimum value and a given scale factor. The probability density function is:

     P(v) = exp( -exp(f*(v-min)))
float min

Minimum number that will be generated

float f

Scale factor for the values

::simulation::random::prng_chiSquared df

Create a command (PRNG) that generates numbers distributed according to the chi-squared distribution with df degrees of freedom. The mean is 0 and the standard deviation is 1.

float df

Degrees of freedom

The package defines the following public procedures for random point sets:

::simulation::random::prng_Disk rad

Create a command (PRNG) that generates (x,y)-coordinates for points uniformly spread over a disk of given radius.

float rad

Radius of the disk

::simulation::random::prng_Sphere rad

Create a command (PRNG) that generates (x,y,z)-coordinates for points uniformly spread over the surface of a sphere of given radius.

float rad

Radius of the disk

::simulation::random::prng_Ball rad

Create a command (PRNG) that generates (x,y,z)-coordinates for points uniformly spread within a ball of given radius.

float rad

Radius of the ball

::simulation::random::prng_Rectangle length width

Create a command (PRNG) that generates (x,y)-coordinates for points uniformly spread over a rectangle.

float length

Length of the rectangle (x-direction)

float width

Width of the rectangle (y-direction)

::simulation::random::prng_Block length width depth

Create a command (PRNG) that generates (x,y,z)-coordinates for points uniformly spread over a block

float length

Length of the block (x-direction)

float width

Width of the block (y-direction)

float depth

Depth of the block (z-direction)

Keywords

math, random numbers, simulation, statistical distribution

Category

Mathematics