Signal labeling in Simulink - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to set the signal label in Simulink.

Simulink

set_param(gco, '[1]', 'SpeedSignal')

Drag options to blanks, or click blank then click option'

AName

BLabelString

CSignalLabel

DSignalName

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'SignalName' instead of 'LabelString'.

Using 'Name' which sets block name, not signal label.

The 'LabelString' parameter is used to set the signal label on Simulink signal lines.

2fill in blank

medium

Complete the code to get the label of a signal line in Simulink.

Simulink

label = get_param([1], 'LabelString')

Drag options to blanks, or click blank then click option'

Agcbh

Bgcb

Cgco

Dgcs

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'gcb' which returns block path, not handle.

Using 'gcs' which returns current system.

The function 'gco' returns the handle of the current object, which is needed to get the signal label.

3fill in blank

hard

Fix the error in the code to label a signal line correctly.

Simulink

set_param([1], 'LabelString', 'OutputSignal')

Drag options to blanks, or click blank then click option'

Agco

Bgcbh

Cgcb

Dgcs

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'gcb' or 'gcbh' which refer to blocks, not signal lines.

Using 'gcs' which refers to the current system.

The function 'gco' returns the handle of the current object, which is the signal line to label.

4fill in blank

hard

Fill both blanks to create a labeled signal line in Simulink.

Simulink

add_line([1], [2], 'autorouting', 'on')

Drag options to blanks, or click blank then click option'

Agcs

Bgcb

C[1, 2]

D[2, 1]

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'gcb' instead of 'gcs' for system.

Swapping port numbers in the vector.

The current system is 'gcs' and the port connectivity is specified as [1, 2] for source and destination ports.

5fill in blank

hard

Fill all three blanks to label a signal line and set its properties.

Simulink

line = add_line([1], [2], 'autorouting', 'on');
set_param(line, '[3]', 'SpeedSignal')

Drag options to blanks, or click blank then click option'

Agcs

B[1, 2]

CName

DLabelString

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'Name' instead of 'LabelString' for signal property.

Incorrect port vector order.

Use 'gcs' for current system, port vector [1, 2], and 'LabelString' to set the signal label property.

Practice

1. What is the main purpose of signal labeling in Simulink models?

easy

A. To increase the simulation speed

B. To change the signal data type automatically

C. To name signals for easier understanding and debugging

D. To create new signal blocks

Solution

1. Step 1: Understand signal labeling purpose

   Signal labeling is used to name signals clearly in a model.

2. Step 2: Identify benefits of labeling

   Labels help with debugging, documentation, and collaboration by making signals easier to recognize.

3. Final Answer:

   To name signals for easier understanding and debugging -> Option C

4. Quick Check:

   Signal labeling = Naming signals [OK]

Hint: Labels make signals easy to identify quickly [OK]

Common Mistakes:

• Thinking labels change signal data types
• Assuming labels speed up simulation
• Confusing labeling with creating blocks

2. Which method correctly adds a label to a signal in Simulink?

easy

A. Right-click the signal and select 'Add Label'

B. Double-click the signal line and type the label

C. Drag a Label block from the library

D. Use the 'Signal Properties' dialog to rename the block

Solution

1. Step 1: Review ways to add labels

   In Simulink, double-clicking a signal line allows direct editing of its label.

2. Step 2: Compare options

   Right-click does not have 'Add Label' option; Label block is separate; renaming block is different from labeling signal.

3. Final Answer:

   Double-click the signal line and type the label -> Option B

4. Quick Check:

   Double-click signal line = Add label [OK]

Hint: Double-click signal line to label it fast [OK]

Common Mistakes:

• Trying to add label via right-click menu
• Confusing signal label with block name
• Dragging unrelated blocks to label signals

3. Given this Simulink model snippet, what label will appear on the signal after running this code?

signal = Simulink.Signal();
signal.CoderInfo.StorageClass = 'ExportedGlobal';
signal.Description = 'Speed signal';
signal.SignalName = 'vehicle_speed';

medium

A. vehicle_speed

B. Speed signal

C. ExportedGlobal

D. Simulink.Signal

Solution

1. Step 1: Understand signal properties

   The 'SignalName' property sets the label shown on the signal line in Simulink.

2. Step 2: Identify label from code

   Here, 'SignalName' is set to 'vehicle_speed', so this is the label that appears.

3. Final Answer:

   vehicle_speed -> Option A

4. Quick Check:

   SignalName property = label shown [OK]

Hint: SignalName property sets the visible label [OK]

Common Mistakes:

• Confusing Description with label
• Using StorageClass as label
• Assuming class name shows as label

4. You tried to label a signal by typing on the line, but the label does not appear. What is the most likely cause?

medium

A. The signal is inside a masked subsystem without label visibility enabled

B. The model is not saved

C. The signal line is too short to display the label

D. The signal data type is incompatible with labeling

Solution

1. Step 1: Consider label visibility rules

   Signals inside masked subsystems may hide labels unless visibility is enabled.

2. Step 2: Evaluate other options

   Signal length does not prevent labeling; saving model does not affect label display; data type does not block labels.

3. Final Answer:

   The signal is inside a masked subsystem without label visibility enabled -> Option A

4. Quick Check:

   Masked subsystem hides labels by default [OK]

Hint: Check masked subsystem label visibility settings [OK]

Common Mistakes:

• Blaming signal length for missing label
• Thinking saving model shows labels
• Assuming data type affects labeling

5. You have multiple signals named 'speed' in different subsystems. How can you label them uniquely to avoid confusion in a large Simulink model?

hard

A. Use the same label 'speed' for all signals to keep consistency

B. Disable signal labels to reduce clutter

C. Rename the blocks instead of labeling signals

D. Add subsystem name as prefix to each signal label, e.g., 'Engine_speed'

Solution

1. Step 1: Understand labeling best practice

   Unique labels help distinguish signals, especially with same base names in different subsystems.

2. Step 2: Apply prefix naming

   Adding subsystem name as prefix (e.g., 'Engine_speed') uniquely identifies each signal.

3. Step 3: Evaluate other options

   Using same label causes confusion; renaming blocks does not label signals; disabling labels removes helpful info.

4. Final Answer:

   Add subsystem name as prefix to each signal label, e.g., 'Engine_speed' -> Option D

5. Quick Check:

   Unique labels = prefix subsystem name [OK]

Hint: Prefix labels with subsystem names for uniqueness [OK]

Common Mistakes:

• Using identical labels causing confusion
• Confusing block names with signal labels
• Removing labels to avoid clutter