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convertDataType

Convert data type for signal in Simulation Data Inspector

Since R2022a

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    Syntax

    convertDataType(sigObj,dataType)

    Description

    convertDataType(sigObj,dataType) converts the data in the Simulink.sdi.Signal object sigObj to the specified data type dataType.

    The convertDataType function supports converting to all built-in data types. For more information, see Data Types Supported by Simulink. When you have a license for Fixed-Point Designer™, you can also convert to fixed-point data types defined using the fixdt function.

    You cannot convert the data type for a signal produced by logging simulation data while the simulation that produces the signal is in progress.

    Warning

    You cannot undo a data type conversion in the Simulation Data Inspector. Some data types allow more precision in the stored data values than others. Conversion to a data type with less precision can result in permanent loss of precision in data values.

    example

    Examples

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    Open Live Script

    Simulate the model vdp while logging outputs using the Dataset format.

    mdl = "vdp";
open_system(mdl)
out = sim(mdl,SaveOutput="on",SaveFormat="Dataset");

    Access the Simulink.sdi.Run object that contains the logged data and metadata in the Simulation Data Inspector.

    run1 = Simulink.sdi.getCurrentSimulationRun(mdl);

    Access the Simulink.sdi.Signal object that contains the data for the signal x1.

    x1Sig = getSignalsByName(run1,"x1");

    Check the DataType property for the signal. The model uses the double data type for the signal.

    x1Sig.DataType
    ans = 
'double'

    Convert the data type for the signal from double to single. You cannot undo a data type conversion in the Simulation Data Inspector. When you convert to a data type with less precision in the stored data values, precision lost due to conversion is permanent. A warning occurs when the data type conversion causes a loss in precision.

    convertDataType(x1Sig,"single");
    Warning: Changing the data type of signal 'x1' from 'double' to 'single' causes precision loss that cannot be undone.

    Check the DataType property for the signal again.

    x1Sig.DataType
    ans = 
'single'
    Open Live Script

    Create time and signal data that represents a sine wave.

    time = 0.01*(0:1000);
time = time';
data = 50*sin(2*pi/3*time);

    By default, MATLAB® creates double data. To represent a scenario where another process creates int32 data you want to analyze in the Simulation Data Inspector, convert the data type for the signal values to int32.

    data = cast(data,"int32");

    Create a timeseries object using the time and data values for the signal. Then, name the timeseries object Sine Wave.

    sigTS = timeseries(data,time);
sigTS.Name = "Sine Wave";

    Import the signal into the Simulation Data Inspector.

    runObj = Simulink.sdi.Run.create("Imported Data","vars",sigTS);

    Access the Simulink.sdi.Signal object with the data values. Then, check the signal data type.

    sigObj = getSignalsByName(runObj,"Sine Wave");
sigObj.DataType
    ans = 
'int32'

    Use the convertDataType function to convert the data type to double. Then, check the signal data type again.

    convertDataType(sigObj,"double");
sigObj.DataType
    ans = 
'double'

    Input Arguments

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    Signal with data to convert, specified as a Simulink.sdi.Signal object.

    Desired data type for signal, specified as a string or a character vector.

    You can convert to any built-in data type by specifying the name for the data type as a string or character vector. For example, to convert to an 8-bit unsigned integer data type, specify the data type as "uint8". For more information about built-in data types and their names, see Data Types Supported by Simulink.

    When you have a license for Fixed-Point Designer, you can also convert to fixed-point data types defined using the fixdt function. To convert to a fixed-point data type, specify the fixdt command as a string or a character vector.

    Example: "int16" specifies conversion to the built-in signed 16-bit integer data type

    Example: "fixdt(1,12,4)" specifies conversion to a fixed-point data type defined using the fixdt function

    Version History

    Introduced in R2022a

    See Also

    Objects

    Functions

    Topics