CD Construct Stochastic Model VI

Control Design VI and Function

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CD Construct Stochastic Model VI

Owning Palette: Stochastic Systems VIs

Installed With: Control Design and Simulation Module

Creates a stochastic state-space representation of a system using the matrices A, B, C, D, G, and H, and the Sampling Time. This VI also produces a stochastic state-space model that specifies the data in symbolic form. The data type you wire to the A, B, C, D, G, or H parameter determines the polymorphic instance to use.

Note  If you do not wire a value to the A, B, C, D, G, H, or symbolic parameters, this VI replaces the unwired parameters with an appropriately-sized vector or matrix of zeros.

This VI uses the CD Verify Stochastic Model Properties VI to verify that the dimensions of the A, B, C, D, G, and H matrices are consistent with each other.

Use the pull-down menu to select an instance of this VI.

 Place on the block diagram  Find on the Functions palette

CD Construct Stochastic Model (Numeric)

Sampling Time (s) specifies the sampling time of the system model and determines whether the model represents a continuous-time or discrete-time system. If the model represents a continuous-time system, Sampling Time must equal zero. If the model represents a discrete-time system, Sampling Time must be greater than zero and equal to the sampling rate, in seconds, of the discrete system. The default is 0.
Note  If you use the inputs to create a continuous-time system, setting the Sampling Time to a value greater than zero does not yield the discrete-time equivalent of the system. You must use the CD Convert Continuous Stochastic to Discrete Stochastic VI to convert the continuous-time system to the discrete-time equivalent of the system.
A specifies the system matrix that describes the dynamics of the states of the system.
B specifies the input matrix that relates the inputs to the states.
C specifies the output matrix that relates the outputs to the states.
D specifies the transmission matrix that relates the inputs to the outputs.
error in describes error conditions that occur before this VI or function runs. The default is no error. If an error occurred before this VI or function runs, the VI or function passes the error in value to error out. This VI or function runs normally only if no error occurred before this VI or function runs. If an error occurs while this VI or function runs, it runs normally and sets its own error status in error out. Use the Simple Error Handler or General Error Handler VIs to display the description of the error code. Use exception control to treat what is normally an error as no error or to treat a warning as an error. Use error in and error out to check errors and to specify execution order by wiring error out from one node to error in of the next node.
status is TRUE (X) if an error occurred before this VI or function ran or FALSE (checkmark) to indicate a warning or that no error occurred before this VI or function ran. The default is FALSE.
code is the error or warning code. The default is 0. If status is TRUE, code is a nonzero error code. If status is FALSE, code is 0 or a warning code.
source specifies the origin of the error or warning and is, in most cases, the name of the VI or function that produced the error or warning. The default is an empty string.
G specifies the matrix that relates the process noise vector to the model states.
H specifies the matrix that relates the process noise vector to the model outputs.
Stochastic State-Space Model returns a mathematical representation of a stochastic state-space model. The data consists of matrices A, B, C, D, G, and H. To access the model data, use the CD Get Data from Stochastic Model VI.
error out contains error information. If error in indicates that an error occurred before this VI or function ran, error out contains the same error information. Otherwise, it describes the error status that this VI or function produces. Right-click the error out front panel indicator and select Explain Error from the shortcut menu for more information about the error.
status is TRUE (X) if an error occurred or FALSE (checkmark) to indicate a warning or that no error occurred.
code is the error or warning code. If status is TRUE, code is a nonzero error code. If status is FALSE, code is 0 or a warning code.
source describes the origin of the error or warning and is, in most cases, the name of the VI or function that produced the error or warning.

CD Construct Stochastic Model (Symbolic)

Sampling Time (s) specifies the sampling time of the system model and determines whether the model represents a continuous-time or discrete-time system. If the model represents a continuous-time system, Sampling Time must equal zero. If the model represents a discrete-time system, Sampling Time must be greater than zero and equal to the sampling rate, in seconds, of the discrete system. The default is 0.
Note  If you use the inputs to create a continuous-time system, setting the Sampling Time to a value greater than zero does not yield the discrete-time equivalent of the system. You must use the CD Convert Continuous Stochastic to Discrete Stochastic VI to convert the continuous-time system to the discrete-time equivalent of the system.
Symbolic A is the symbolic representation of the system matrix that describes the dynamics of the states of the system.
Symbolic B is the symbolic representation of the input matrix of the system that relates the inputs to the states.
Symbolic C is the symbolic representation of the output matrix that relates the outputs to the states.
Symbolic D is the symbolic representation of the transmission matrix that relates the inputs to the outputs.
error in describes error conditions that occur before this VI or function runs. The default is no error. If an error occurred before this VI or function runs, the VI or function passes the error in value to error out. This VI or function runs normally only if no error occurred before this VI or function runs. If an error occurs while this VI or function runs, it runs normally and sets its own error status in error out. Use the Simple Error Handler or General Error Handler VIs to display the description of the error code. Use exception control to treat what is normally an error as no error or to treat a warning as an error. Use error in and error out to check errors and to specify execution order by wiring error out from one node to error in of the next node.
status is TRUE (X) if an error occurred before this VI or function ran or FALSE (checkmark) to indicate a warning or that no error occurred before this VI or function ran. The default is FALSE.
code is the error or warning code. The default is 0. If status is TRUE, code is a nonzero error code. If status is FALSE, code is 0 or a warning code.
source specifies the origin of the error or warning and is, in most cases, the name of the VI or function that produced the error or warning. The default is an empty string.
Symbolic G is the symbolic representation of the matrix that relates the process noise to the model states.
Symbolic H is the symbolic representation of the matrix that relates the process noise to the model outputs.
Variables contains the name and value of each variable.
Name is a variable name this VI uses to define the data of the system model. Variable names can be a combination of letters and numbers. A variable name that begins with a capital letter E can produce unpredictable errors if parts of the original string represent numbers like 1E–2. Avoid terms beginning with E in such cases.
Value is the numeric value this VI associates with the variable. The VI uses this value to evaluate the model.
Stochastic State-Space Model returns a mathematical representation of a stochastic state-space model. The data consists of matrices Symbolic A, Symbolic B, Symbolic C, Symbolic D, Symbolic G, and Symbolic H. To access the model data, use the CD Get Data from Stochastic Model VI.
error out contains error information. If error in indicates that an error occurred before this VI or function ran, error out contains the same error information. Otherwise, it describes the error status that this VI or function produces. Right-click the error out front panel indicator and select Explain Error from the shortcut menu for more information about the error.
status is TRUE (X) if an error occurred or FALSE (checkmark) to indicate a warning or that no error occurred.
code is the error or warning code. If status is TRUE, code is a nonzero error code. If status is FALSE, code is 0 or a warning code.
source describes the origin of the error or warning and is, in most cases, the name of the VI or function that produced the error or warning.
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