Migrating from Metrics Dashboard to Model Maintainability Dashboard

The Model Maintainability Dashboard collects metric data from the model design artifacts in a project to help you assess the size, architecture, and complexity of your design. If you currently use the Metrics Dashboard to only analyze your model size, architecture, and complexity, then you can use the Model Maintainability Dashboard instead. The Model Maintainability Dashboard collects metrics without compiling the model and automatically identifies metric results that are outdated due to changes in the project. You can migrate to the Model Maintainability Dashboard by creating a project for your model, fixing artifact traceability issues, and updating code you use to collect and display metric results.

The Model Maintainability Dashboard does not support all of the capabilities available in the Metrics Dashboard. For more information, see Limitations. If you are using one of these capabilities, you should continue to use the Metrics Dashboard.

Advantages of the Model Maintainability Dashboard

The Metrics Dashboard runs on an individual model or subsystem and requires a computationally intensive, compile-based analysis for many metrics.

The Model Maintainability Dashboard can analyze Simulink^® models, Stateflow^® charts, and MATLAB^® code in your project to help you determine if parts of a design are too complex and need to be refactored. The Model Maintainability Dashboard can:

Collect metrics without compiling the model.
Trace the relationships between models and related design artifacts.
Automatically identify metric results that are outdated due to changes in the project.
Aggregate metrics across software units in software components. You can explicitly specify the boundaries of aggregation by using project labels to categorize the units and components.
Provide metrics, like the Halstead Difficulty, that are not available in the Metrics Dashboard. For an overview of the metrics, see Model Maintainability Metrics.
Generate a report that contains the metric results.

Additionally, the Model Maintainability Dashboard uses the same dashboard user interface and metric API as the Model Testing, SIL Code Testing, and PIL Code Testing dashboards.

For an overview of the dashboard metrics and results, see Explore Metric Results, Monitor Progress, and Identify Issues.

How to Migrate to the Model Maintainability Dashboard

You can migrate to the Model Maintainability Dashboard by setting up a project for your model, fixing artifact traceability issues, and updating code that you use to collect and display metric results.

Create and Open Project

To use the Model Maintainability Dashboard, your models must be inside a project. The project folder, and referenced project folders, define the scope of the artifacts that the dashboard metrics analyze and help the dashboard to detect when metric results become outdated. If you already have a project that contains your model, open the project. Otherwise, you can create a project directly from your model or create an empty project. For more information, see Create Project to Use Model Design and Model Testing Dashboards.

Open Dashboard and Enable Artifact Tracing

After you open your project, open the Model Maintainability Dashboard. On the Project tab, in the Tools section, click Model Design Dashboard.

When you open a dashboard for a project for the first time, the Enable Artifact Tracing dialog box opens and prompts you to enable artifact tracing for the project. The dashboard uses artifact tracing to create a digital thread that monitors the project for changes and identifies if the changes invalidate the metric results. Click Enable and Continue to create a digital thread for the project.

The Dashboard window opens and automatically opens a Model Maintainability dashboard tab for a model in the project. The Dashboard window provides a centralized location where you can open dashboards for the models in your project, view metric results, analyze affected artifacts, and generate reports on the quality and compliance of the artifacts in your project. For more information, see Analyze Your Project With Dashboards.

Review Units and Components

Your models appear as units and components in the Project panel in the Model Maintainability Dashboard. A unit is a functional entity in your software architecture that you can execute and test independently or as part of larger system tests. A component is an entity that integrates multiple testable units together. By default, the dashboard considers each Simulink model inside your project folder as a unit and each System Composer™ architecture model as a component. The dashboard categorizes models as units and components because software development standards, such as ISO 26262-6, define objectives for unit testing. For information, see Categorize Models in Hierarchy as Components or Units.

If you want to exclude certain models from the dashboard, specify which models are units or components by labeling them in your project and configuring the dashboard to recognize the label, as shown in Specify Models as Components and Units. If you expect a model to appear in the Project panel and it does not, see Fix Artifact Issues.

Fix Artifact Issues

The dashboard finds artifact issues in the project that lead to unsaved information, portability issues, or ambiguous relationships between artifacts. These issues can cause certain artifacts to not appear in the dashboard, which can lead to incorrect metric results. You can investigate artifact issues by using the Artifact Issues tab in the Dashboard window. The warning and error icons in the dashboard toolstrip indicate the artifact issues. Investigate the issues by clicking the Artifact Issues button. For information on how to view artifact issues, see View Artifact Issues in Project. For information on how to fix artifact issues, see Resolve Missing Artifacts, Links, and Results.

Review Dashboard Results

The Model Maintainability Dashboard collects metric data from the model design artifacts in your project to help you assess the size, architecture, and complexity of your design.

For some metrics, you might see a difference between the Metrics Dashboard and Model Maintainability Dashboard results. For a comparison of the metrics, see the metric comparison in Choose Which Metrics to Collect.

To view information about a metric and how the dashboard calculates the metric value, point to a widget, then point to the three dots in the top-right corner of the widget, and click the Help icon .

For an overview the Model Maintainability Dashboard and metrics, see Monitor Design Complexity Using Model Maintainability Dashboard and Model Maintainability Metrics.

Update Programmatic Metric Collection

For the Metrics Dashboard, you use a slmetric.Engine object to collect metric results. For the Model Maintainability Dashboard, you use a metric.Engine object to collect metric results. The way you collect metrics programmatically is similar for both dashboards, but you need to update your code. This table shows the programmatic differences in how you collect metric results for a model, in this case the number of Simulink blocks in a model named myModel.

Functionality	`slmetric.Engine` API for Metrics Dashboard	`metric.Engine` API for Model Maintainability Dashboard	More Information
Creating Metric Engine	metric_engine = slmetric.Engine();	metric_engine = metric.Engine();	See `metric.Engine`.
Specifying Scope of Analysis	setAnalysisRoot(metric_engine,'Root','myModel','RootType','Model');	For the Model Maintainability Dashboard, you do not need to set an analysis root. By default, the `execute` function analyzes the units and components in your project. If you only want to collect metrics for a specific model, you can specify a model using the `ArtifactScope` name-value argument of the `execute` function, as shown below.	See the `execute` function.
Collecting Metric Results	execute(metric_engine,'mathworks.metrics.SimulinkBlockCount');	model = [which("myModel.slx"),"myModel"]; execute(metric_engine,"slcomp.SimulinkBlocks", ... ArtifactScope = model);	See the `execute` function. Both dashboards have metrics for model size, architecture, and complexity. However, for some metrics, you might see a difference between the Metrics Dashboard and Model Maintainability Dashboard results. For a comparison of the metrics, see the metric comparison in Choose Which Metrics to Collect.
Accessing Metric Results	results = getMetrics(metric_engine,'mathworks.metrics.SimulinkBlockCount');	results = getMetrics(metric_engine,"slcomp.SimulinkBlocks");	See the `getMetrics` function.
Getting Available Metrics	modelMetrics = slmetric.metric.getAvailableMetrics();	maintainabilityMetrics = getAvailableMetricIds(metric_engine, ... App="DashboardApp", ... Dashboard="ModelMaintainability");	See the `getAvailableMetricIds` function. For details on the model maintainability metrics, see Model Maintainability Metrics.

For more information, see metric.Engine and Collect Model Maintainability Metrics Programmatically.

Choose Which Metrics to Collect

The Model Maintainability Dashboard provides size, architecture, and complexity metrics that are similar to the Size Metrics and Architecture Metrics in the Metrics Dashboard. Some Metrics Dashboard metrics, like the Compliance Metrics and Readability Metrics, are not supported yet. For more information, see Limitations.

For some metrics, you might see a difference between the Metrics Dashboard and Model Maintainability Dashboard results. These tables summarize how metrics in the Metrics Dashboard relate to metrics in the Model Maintainability Dashboard.

Size Metrics

Metric in Metrics Dashboard	Version of Metric in Model Maintainability Dashboard
Simulink Block Metric	Overall Blocks Simulink Blocks Simulink Blocks Distribution The Model Maintainability Dashboard also provides other Simulink Architecture metrics that are not available in the Metrics Dashboard.
Subsystem Metric	None
Library Link Metric	None
Effective Lines of MATLAB Code Metric	Overall MATLAB Effective Lines of Code (eLOC) MATLAB Effective Lines of Code (eLOC) MATLAB Effective Lines of Code (eLOC) Distribution
Stateflow Chart Objects Metric	The Model Maintainability Dashboard provides other Stateflow Architecture metrics that are not available in the Metrics Dashboard.
Lines of Code for Stateflow Blocks Metric
Subsystem Depth Metric	The Model Maintainability Dashboard provides other Component Structure and Interfaces metrics that are not available in the Metrics Dashboard.
Input Output Metric	Input and Output Component Interface Ports
Explicit Input Output Metric	Input and Output Component Interface Ports
File Metric	None
MATLAB Function Metric	The Model Maintainability Dashboard provides other MATLAB Architecture metrics.
Model File Count	None
Parameter Metric	None
Stateflow Chart Metric	The Model Maintainability Dashboard provides other Stateflow Architecture metrics that are not available in the Metrics Dashboard.

Architecture Metrics

Metric in Metrics Dashboard	Version of Metric in Model Maintainability Dashboard
Cyclomatic Complexity Metric	Overall Design Cyclomatic Complexity Simulink Design Cyclomatic Complexity Stateflow Design Cyclomatic Complexity MATLAB Design Cyclomatic Complexity
Clone Content Metric	None
Clone Detection Metric	None
Library Content Metric	None

Limitations

The Model Maintainability Dashboard does not support some capabilities in the Metrics Dashboard.

Dashboard for Subsystem

The Model Maintainability Dashboard does not provide the ability to open a dashboard directly on a subsystem and display the subsystem metric results in the dashboard widgets. However, when you click a widget in the Model Maintainability Dashboard, the app provides a table of detailed metric results for individual Simulink model layers, MATLAB functions and methods, and Stateflow objects. For an example of the detailed metric results in the Model Maintainability Dashboard, see the Metric Details in Monitor Design Complexity Using Model Maintainability Dashboard. If you need the dashboard widgets to display information for a subsystem, use the Metrics Dashboard.

Modeling Guideline Compliance

The Model Maintainability Dashboard does not provide compliance metrics for Model Advisor check issues, code analyzer warnings, or Simulink diagnostic warnings. If you use the Modeling Guideline Compliance group in the Metrics Dashboard, Compliance Metrics, or the Readability Metrics, use the Metrics Dashboard.

Modeling Guideline Compliance section with metric results for high-integrity and MAAB checks

Actual Reuse and Potential Reuse

The Model Maintainability Dashboard does not provide architecture metrics for actual and potential model component and subcomponent reuse. If you use the Actual Reuse or Potential Reuse widgets in the Metrics Dashboard, or the metrics Clone Content Metric, Clone Detection Metric, or Library Content Metric, use the Metrics Dashboard.

Architecture section with metric results for Actual Reuse and Potential Reuse of modeling components

Custom Metrics

By default, the Model Maintainability Dashboard does not provide the ability to create custom metrics. If you have custom metrics, like MATLAB classes that inherit from the abstract base class slmetric.metric.Metric and Compliance Metrics for Model Advisor Configurations, contact MathWorks^® Consulting Services for help creating custom metrics for the Model Maintainability Dashboard. Otherwise, use the Metrics Dashboard.

Custom Dashboard Layout

The Model Maintainability Dashboard does not provide the ability to customize the dashboard layout or other dashboard functionality, like compliance thresholds. To see an example of the dashboard layout for the Model Maintainability Dashboard, see Monitor Design Complexity Using Model Maintainability Dashboard. If you require a different layout for your dashboard widgets, containers, and custom widgets, use the Metrics Dashboard.