For most input test cases, you try to minimize the number of time points. The signal data you load includes samples with ramps and discontinuities.
Typically when importing a test case data, you want to minimize the number of time points. The test data focuses on discontinuities in the signal data.
Create a signal that has ramps and steps. In other words, the signal has one or more discontinuities.
Create the signal using the fewest points possible.
Have the Simulink® solver execute at the specified discontinuities.
To import this signal in Simulink, use a From Workspace, From File, or Signal Builder block, all of which support zero-crossing detection.
You can load data of these types:
A structure array containing data for all input ports.
Empty matrix — Use an empty matrix for ports for which you want to use ground values, without having to create data values.
Specify a time vector and signal values, but specify only the time steps at points where the shape of the output jumps. For details about specifying a time vector, see Specify Time Data.
Use any of the input data formats described in Loading the Data, except for MATLAB® time expressions.
The following is an example of test case data:
The following two examples use this test case data.
Open the model
Enable zero-crossing detection. In the From Workspace block dialog, select Enable zero-crossing detection. Zero-crossing detection allows you to capture discontinuities accurately.
Create a signal structure for the test case. At each discontinuity, enter a duplicate entry in the time vector, which generates a zero crossing and forces the variable-step solver to take a time step at this exact time. For details, see Load Data Using the From Workspace Block.
var structure representing the
var.time = [0 1 1 5 5 8 8 10]; var.signals.values = [0 0 2 2 2 3 3 3]'; var.signals.dimensions = 1;
To import the test case structure, in the From Workspace
block dialog box, in the Data parameter, specify
Simulate the model. The Scope block reflects the test case data.
Instead of using a From Workspace block, you can use a Signal Builder block to either:
Create a signal interactively
Import a signal from a MAT-file
Create a structure and save it in a MAT-file:
var.time = [0 1 1 5 5 8 8 10]; var.signals.values = [0 0 2 2 2 3 3 3]'; var.signals.dimensions = 1; var.signals.label = 'var'; save var.mat var
Open the Signal Builder dialog box by double-clicking the Signal Builder block.
Select File > Import From File menu item,
and select the
In the Select parameter, select
existing dataset. In the Data to Import section,
select the Select All check box. Confirm the
selection and click OK.
The Signal Builder block display reflects the test case data.