Work with Arrays of Buses

Set Up Model for Arrays of Buses

Setting up a model to use an array of buses usually involves these basic tasks:

Define the array of buses (seeDefine an Array of Buses).
Add a subsystem for performing iterative processing on each element of the array of buses. For example, use aFor Each Subsystemblock or anIteratorblock. Connect the array of buses signal from theConcatenateblock to the iterative processing subsystem. SeePerform Iterative Processing.
Model your scalar algorithm within the iterative processing subsystem (for example, a For Each subsystem).
1. Operate on the array of buses (usingSelectorandAssignmentblocks).
2. Use theBus SelectorandBus Assignmentblocks to select elements from, or assign elements to, a scalar bus within the subsystem.
SeeAssign Values into an Array of BusesandSelect Bus Elements from an Array of Buses.
Optionally, import or log array of buses data. SeeImport Array of Buses DataandLog Arrays of Buses

The resulting model includes these components.

Perform Iterative Processing

You can perform iterative processing on the bus signal data of an array of buses using blocks such as aFor Each Subsystemblock, aWhile Iterator Subsystemblock, or aFor Iterator Subsystemblock. You can use one of these blocks to perform the same kind of processing on:

Each bus in the array of buses
A selected subset of buses in the array of buses

Assign Values into an Array of Buses

To assign a value to a signal within an array of buses, use:

ABus Assignment块赋值总线元素
AnAssignmentblock to assign the bus to the array of buses

Use anAssignmentblock to assign values to specified elements in a bus array.

For example, in thesldemo_bus_arraysmodel, theAssignmentblock assigns the value to the first element of the array of buses.

To assign bus elements within a bus signal, use theBus Assignmentblock. The input for theBus Assignmentblock must be a scalar bus signal.

Assign into Arrays of Buses

You can use aBus Assignmentblock to assign or fully replace a nested bus that is an array of buses. To assign the data for a nested bus inside an array of buses or to make a partial assignment to certain elements with the array of buses, you can use aMATLAB Functionblock.

For example, suppose that you have this bus structure:

The bus has achildrenelement, which is a sub-bus array. This example shows how to assign to elementcand to elementa. TheInportandOutportblocks use theParentbus object. To define the assignments, this example uses aMATLAB Functionblock, because you cannot assign into elementausing aBus AssignmentorAssignmentblock.

TheMATLAB Functionblock uses this function code for making the assignments:

functiony = fcn(u) y = u; y.c = false;foridx = 1:length(y.children) y.children(idx).a = int32(zeros(5, 1));end

Select Bus Elements from an Array of Buses

To select a signal within an array of buses, use a:

Selectorblock to find the appropriate bus within the array of buses.
Bus Selectorblock to select the signal.

Use aSelectorblock to select elements of an array of buses. The input array of buses can have any dimension. The output bus signal of theSelector块是一个选择或再保险ordered set of elements from the input array of buses.

For example, thesldemo_bus_arraysmodel uses Selector blocks to select elements from the array of buses signal that theAssignmentandFor Each Subsystemblocks outputs. In this example, here is the Block Parameters dialog box for theSelectorblock that selects the first element:

To select bus elements within a bus signal, use theBus Selectorblock. The input for theBus Selectorblock must be a scalar bus signal.

Import Array of Buses Data

Use a rootInportblock to import (load) an array of structures of MATLAB^®timeseriesobjects for an array of buses. You can import partial data into the array of buses.

For details, seeImport Array of Buses Data.

You cannot use aFrom WorkspaceorFrom Fileblock to import data for an array of buses.

Log Arrays of Buses

To export an array of buses signal, mark the signal for signal logging. For more information, seeSave Run-Time Data from Simulation.

Note

金宝app^®does not log signals inside referenced models in rapid accelerator mode.

To access the signal logging data for a specific signal in an array of buses, navigate through the structure hierarchy and specify the index to the specific signal. For details, seeAccess Array of Buses Signal Logging Data.

Initialize Arrays of Buses

To specify a unique initial value for each of the individual signals in an array of buses, you can use an array of initial condition structures. Each structure in the array initializes one of the buses.

Here is an example that shows how to initialize an array of buses. Suppose that you define the bus typesMyDataandPressureBus.

Suppose that you set the data type of the signal elementtemperaturetoint16, and the data type of the elementss1ands2todouble.

To specify initial conditions for an array of buses, you can create a variable whose value is an array of initial condition structures.

initValues(1).temperature = int16(5); initValues(1).pressure.s1 = 9.87; initValues(1).pressure.s2 = 8.71; initValues(2).temperature = int16(20); initValues(2).pressure.s1 = 10.21; initValues(2).pressure.s2 = 9.56; initValues(3).temperature = int16(35); initValues(3).pressure.s1 = 8.98; initValues(3).pressure.s2 = 9.17;

The variableinitValuesprovides initial conditions for a signal that is an array of three buses. You can useinitValuesto specify theInitial conditionparameter of a block such asUnit Delay.

Alternatively, you can use a single scalar structure to specify the same initial conditions for all the buses in the array.

initStruct.temperature = int16(15); initStruct.pressure.s1 = 10.32; initStruct.pressure.s2 = 9.46;

If you specifyinitStructin theInitial conditionparameter of a block, each bus in the array uses the same initial value,15, for the signal elementtemperature. Similarly, the buses use the initial value10.32for the elementpressure.s1and the value9.46for the elementpressure.s2.

To create an array of structures for a bus that uses a large hierarchy of signal elements, consider using the functionSimulink.Bus.createMATLABStruct.

This example shows how to initialize a nested array of buses. Create an initial condition structure for a complicated signal hierarchy that includes nested arrays of buses.

In the Bus Editor, create the bus objectsMyDataandPressureBus.
In the hierarchy pane, select the bus elementpressure. Set theDimensionsproperty to[1 3].
Create an array of four initialization structures by using the functionSimulink.Bus.createMATLABStruct. Store the array in the variableinitStruct. Initialize all the individual signals to the ground value,0.
```
initStruct=Simulink.Bus.createMATLABStruct('MyData',[],[1 4]);
```
In the base workspace, double-click the variableinitStructto view it in the variable editor.
The four structures in the array each have the fieldstemperatureandpressure.
To inspect apressure, double-click one of the fields.
The value of each of the fourpressurefields is an array of three substructures. Each substructure has the fieldss1ands2.
To provide unique initialization values for the signals in an array of buses, you can specify the values manually using the variable editor.
Alternatively, you can write a script. For example, to access the fields1of the second substructurepressure在third structure ofinitStruct, use this code:
```
initStruct(3).pressure(2).s1 = 15.35;
```