dsp.MatFileWriter

Write MAT file

Description

The dsp.MatFileWriter System object™ writes data to a V7.3 MAT file.

To write data to a V7.3 MAT file:

  1. Create the dsp.MatFileWriter object and set its properties.

  2. Call the object with arguments, as if it were a function.

To learn more about how System objects work, see What Are System Objects? (MATLAB).

Creation

Description

mfw = dsp.MatFileWriter returns a MAT file writer System object, mfw, that writes data to a V7.3 MAT file.

example

mfw = dsp.MatFileWriter(fname,vname) returns a MAT file writer System object with the Filename property set to fname and the VariableName property set to vname.

mfw = dsp.MatFileWriter(Name,Value) returns a MAT file writer System object with each specified property set to the specified value. Unspecified properties have default values.

Properties

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Unless otherwise indicated, properties are nontunable, which means you cannot change their values after calling the object. Objects lock when you call them, and the release function unlocks them.

If a property is tunable, you can change its value at any time.

For more information on changing property values, see System Design in MATLAB Using System Objects (MATLAB).

Specify the name of a MAT file as a character vector or a string scalar. Specify the full path for the file only if the file is not on the MATLAB® path.

Name of the variable to which to write, returned as a character vector or a string scalar. This variable is stored in the MAT file. You cannot overwrite a variable that is already in an existing MAT file.

Usage

Syntax

Description

example

mfw(data) writes one frame of data to the variable stored in the MAT file. The variable is assumed to be N-dimensional and a MATLAB built-in data type. The data is written to the file by concatenating along the first dimension.

Input Arguments

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Data to be written to the MAT file, specified as a scalar, vector, or a matrix. The data can be an N-dimensional array.

Data Types: single | double | int8 | int16 | int32 | int64 | uint8 | uint16 | uint32 | uint64

Object Functions

To use an object function, specify the System object as the first input argument. For example, to release system resources of a System object named obj, use this syntax:

release(obj)

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stepRun System object algorithm
releaseRelease resources and allow changes to System object property values and input characteristics
resetReset internal states of System object

Examples

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Note: This example runs only in R2016b or later. If you are using an earlier release, replace each call to the function with the equivalent step syntax. For example, myObject(x) becomes step(myObject,x).

First, create a variable name.

filename = [tempname '.mat'];

Next, write that variable to a MAT-file.

mfw = dsp.MatFileWriter(filename,'VariableName','originalData');
for i = 1:10
    originalData = rand(4,2);
    mfw(originalData);
end
release(mfw); % This will close the MAT file

Finally, load the variable back into MATLAB.

data = load(filename,'originalData');

Plot the data.

plot(data.originalData);

See Also

System Objects

Introduced in R2012b