Simulink.SubsysDataLogs

(Removed) Access data for signals logged inside subsystems

Support for the Simulink.SubsysDataLogs object has been removed. Use another supported format, such as Dataset, instead. For more information, see Version History.

Description

The Simulink.SubsysDataLogs object contains the data for each signal, mux, and bus logged inside a subsystem.

Creation

Prior to R2016a, you could configure a model to log data using the ModelDataLogs format. Simulating a model with the Signal logging format parameter set to ModelDataLogs created a Simulink.ModelDataLogs object that contained the data for all logged signals. You could specify the name for the ModelDataLogs object using the Signal logging name parameter.

A ModelDataLogs object contains a Simulink.SubsysDataLogs object for each subsystem in the model that contains logged data.

Properties

Logged Data Properties

The Simulink.SubsysDataLogs object contains properties with the signal data logged inside the subsystem the object represents. The number, type, and names of the properties that contain logged data depend on subsystem contents and the logging configuration.

Property Name Source	Logged Data Source	Value
Model name	Top model or model reference	Simulink.ModelDataLogs
Subsystem name	Subsystem	Simulink.SubsysDataLogs
Signal name	Signal	Simulink.Timeseries
Mux or virtual bus name	Mux or virtual bus	Simulink.TSArray
Bus object	Nonvirtual bus	Simulink.TSArray

Subsystem Properties

Name — Name of subsystem represented by object

character vector

Name of subsystem represented by object, specified as a character vector.

Object Functions

unpack	(Removed) Extract signal data from ModelDataLogs, SubsysDataLogs, or TSArray object into workspace variables
who	(Removed) List names of objects inside ModelDataLogs, SubsysDataLogs, or TSArray object
whos	(Removed) List name and type of objects inside ModelDataLogs, SubsysDataLogs, or TSArray object

Version History

Introduced before R2006a

R2025a: Removed

Data stored in the ModelDataLogs format, including data stored in Simulink.ModelDataLogs, Simulink.Timeseries, Simulink.TSArray, and Simulink.SubsysDataLogs objects, is no longer supported.

R2024b: To be removed

The Simulink.SubsysDataLogs object will be removed in a future release.

R2024b: Converting data logged in ModelDataLogs format to Dataset format no longer supported

The convertToDataset function has been removed, and the Simulink.SimulationData.Dataset object can no longer convert ModelDataLogs format to Dataset format. To convert data logged in ModelDataLogs format to Dataset format, use a version of Simulink prior to the R2024b release.

R2022b: Loading data saved in the ModelDataLogs format no longer supported

Starting in R2022b, you can no longer load data stored in the ModelDataLogs format, including data stored in Simulink.Timeseries, Simulink.TSArray, and Simulink.SubsysDataLogs objects.

For scripts that simulate a model created in a release earlier than R2016a that uses ModelDataLogs format for logging, you can convert data stored in the ModelDataLogs format to the Dataset format.

Converting a model from using ModelDataLogs format to using Dataset format can require that you modify your existing models and code in callbacks, functions, scripts, or tests. This table identifies possible issues to address after converting to Dataset format.

Possible Issue After Conversion to Dataset Format	Solution
Code in existing callbacks, functions, scripts, or tests that used the ModelDataLogs programmatic interface to access data can result in an error.	Check for code that uses ModelDataLogs format access methods. Update that code to use Dataset format access methods. For example, suppose that existing code includes this line. logsout.('Subsystem Name').X.data Replace that code with a Dataset access function. get(logsout,"x").Values.data
Mux block signal names are lost.	The Dataset format treats Mux block signals as a vector. To identify signals by signal names, replace Mux blocks with Bus Creator blocks.
Signal Viewer cannot be used for signal logging.	The software does not log signal logging data in the Signal Viewer. Use the signal logging output variable to view the logged data.
The unpack function generates an error.	The unpack function, which is supported for Simulink.ModelDataLogs and Simulink.SubsysDataLogs objects, is not supported for Simulink.SimulationData.Dataset objects. For example, suppose the data in mlog has three fields: x, y, and z. For ModelDataLogs format data, the mlog.unpack function creates three variables in the base workspace. For Dataset format data, the get function accesses data by name. x = get(logsout,"x").Values
The ModelDataLogs and Dataset formats have different naming rules for unnamed signals.	If necessary, add signal names. In ModelDataLogs format, for an unnamed signal coming from a block, the software assigns a name in the form SL_BlockName+<portIndex>, for example, SL_Gain1. In Dataset format, elements do not need a name, so the software leaves the signal name empty. For both ModelDataLogs and Dataset formats, the software assigns the same name to unnamed signals that come from Bus Selector blocks.
Test points in referenced models are not logged.	Consider enabling signal logging for test points in a referenced model.
Script uses who or whos functions.	Consider using find instead.

R2021a: Loading data saved in the ModelDataLogs format will not be supported

When you load data that uses the ModelDataLogs format as input for simulation, the software issues a warning that support for loading data in the ModelDataLogs format will be removed in a future release.

R2020b: Loading data saved in the ModelDataLogs format will not be supported

In a future release, the ability to load data that uses the ModelDataLogs format as input for simulation will be removed.

R2016a: Logging data using ModelDataLogs format no longer supported

Starting in R2016a, you can no longer log data using the ModelDataLogs format, and signal logging always uses the Dataset format. When you open a model from a previous release that had logged data using ModelDataLogs format, the model configuration parameters are updated to log data using the Dataset format instead.

You can still use and access data logged using the ModelDataLogs format in previous releases, including data in Simulink.SubsysDataLogs, Simulink.TSArray, and Simulink.Timeseries objects. You can also convert data saved in the ModelDataLogs format to the Dataset format, which can simplify data processing.