WOLFRAM SYSTEMMODELER

TruncatedNormalNoise

Noise generator with truncated normal distribution

Wolfram Language

In[1]:=
SystemModel["Modelica.Blocks.Noise.TruncatedNormalNoise"]
Out[1]:=

Information

This information is part of the Modelica Standard Library maintained by the Modelica Association.

A summary of the common properties of the noise blocks is provided in the documentation of package Blocks.Noise. This TruncatedNormalNoise block generates reproducible, random noise at its output according to a truncated normal distribution. This means that normally distributed random values are truncated to the band y_min ... y_max. Measurement noise has often this distribution form. By default, the standard parameters of the truncated normal distribution are derived from y_min ... y_max:

mean value = (y_max + y_min)/2,
standard deviation = (y_max - y_min)/6 (= 99.7 % of the non-truncated normal distribution are within y_min ... y_max).

For an example see NoiseExamples.Distributions. By default, two or more instances produce different, uncorrelated noise at the same time instant. The block can only be used if on the same or a higher hierarchical level, model Blocks.Noise.GlobalSeed is dragged to provide global settings for all instances.

Parameters (12)

samplePeriod

Value:

Type: Period (s)

Description: Period for sampling the raw random numbers

enableNoise

Value: globalSeed.enableNoise

Type: Boolean

Description: =true: y = noise, otherwise y = y_off

y_off

Value: 0.0

Type: Real

Description: y = y_off if enableNoise=false (or time

useGlobalSeed

Value: true

Type: Boolean

Description: = true: use global seed, otherwise ignore it

useAutomaticLocalSeed

Value: true

Type: Boolean

Description: = true: use automatic local seed, otherwise use fixedLocalSeed

fixedLocalSeed

Value: 1

Type: Integer

Description: Local seed (any Integer number)

startTime

Value: 0.0

Type: Time (s)

Description: Start time for sampling the raw random numbers

localSeed

Value:

Type: Integer

Description: The actual localSeed

y_min

Value:

Type: Real

Description: Lower limit of y

y_max

Value:

Type: Real

Description: Upper limit of y

mu

Value: (y_max + y_min) / 2

Type: Real

Description: Expectation (mean) value of the normal distribution

sigma

Value: (y_max - y_min) / 6

Type: Real

Description: Standard deviation of the normal distribution

Connectors (1)

y

Type: RealOutput

Description: Connector of Real output signal

Components (1)

globalSeed

Type: GlobalSeed

Description: Definition of global seed via inner/outer

Used in Examples (1)

Distributions

Modelica.Blocks.Examples.NoiseExamples

Demonstrates noise with different types of distributions