MATLAB: ‘From Workspace’ block does not support importing matrices of type ‘uint8’

frommatrixsimulinkuint8workspace

I'm having some trouble using the 'From Workspace' block to output data of type 'uint8'. It seems like the block does not accept variables in the base workspace that are of type 'uint8'. One solution would be to use a data type conversion block, but I'd like to avoid this.

How can I configure the 'From Workspace' block to output 'uint8'?

Best Answer

This is mainly because the 'From Workspace' block can only import matrices that are 'Non-Complex' and of type 'Double'.

I understand that you are unable to use the 'Data Type Conversion' block, but that would be the simplest workaround at this time.

I have notified our development team of the error you are encountering when trying to import 'uint8' data using the 'From Workspace' block and they will consider providing support for the same in a future release of MATLAB.

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MATLAB: Does “setVariable” in Simulink Test not update variables

In R2019b, the behavior of "setVariable" is modified such that it overrides only model variables (as opposed to MATLAB variables).

I attached a simpler model ("SimpleVars_R2019b.slx") to help illustrate this. This model has two "From Workspace" blocks, one set to "a" and one set to "evalin('base', 'b')".

If you call "findVars" on this model, only "a" is considered to be a model variable, even though both output their timeseries when run:

>> vars = Simulink.findVars('SimpleVars_R2019b')
vars = 
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      SourceType: 'base workspace'
           Users: {'SimpleVars_R2019b/From↵Workspace'}

The R2019b behavior provides stricter control of overrides and achieves parity with other Simulink tools. You will need to update the model to use variables which are recognized by Simulink.

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You should observe that "setVariable" updates all of the variables now.

MATLAB: Do I get an error about evaluating an expression with the MATLAB built-in data type functions like ‘uint8’ when importing ARXML for an AUTOSAR 4.0 software component

Simulink imports AUTOSAR data types from the ARXML according to the rules mentioned here:

https://www.mathworks.com/help/ecoder/autosar/data-types.html#btdawtt

If you use an application data type name that matches a Simulink built-in data type (double, single, int8, uint8, int16, uint16, int32, uint32, boolean) the imported Simulink.AliasType now shadows the built-in MATLAB functions that might be used to configure the Simulink model created for the imported AUTOSAR software component. In general, application data type names should abstract away from implementation details such as signedness or size, and typically have physically relevant names like EngSpeed. If you know you want to use a data type that directly maps to a Simulink type (or really any other standard platform type), reference an implementation type/platform type rather than an application type.

Best Answer

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MATLAB: Does “setVariable” in Simulink Test not update variables

MATLAB: Do I get an error about evaluating an expression with the MATLAB built-in data type functions like ‘uint8’ when importing ARXML for an AUTOSAR 4.0 software component

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