readall

R2026b

Read all audio files from datastore

Syntax

data = readall(ADS)

data = readall(ADS,UseParallel=parmode)

Description

data = readall(ADS) reads all audio files from the datastore.

If all the data in the datastore does not fit in memory, then readall returns an error.

data = readall(ADS,UseParallel=parmode) reads the data in parallel if parmode is "on" or "auto" (requires Parallel Computing Toolbox™).

Examples

Read All Data in Audio Datastore

Specify the file path to the audio samples included with Audio Toolbox™. Create an audio datastore that points to the specified folder.

folder = fullfile(matlabroot,'toolbox','audio','samples');
ADS = audioDatastore(folder);

Read all the data in the datastore.

readall(ADS)

ans = 39×1 cell array
    { 539648×1  double}
    { 320512×4  double}
    { 227497×1  double}
    {  48000×1  double}
    {   8000×1  double}
    { 685056×1  double}
    { 882688×2  double}
    {  24000×1  double}
    { 175104×1  double}
    {1116288×2  double}
    {1215360×2  double}
    { 263304×16 double}
    { 100868×1  double}
    { 180224×1  double}
    {  32768×1  double}
    { 192150×1  double}
      ⋮

Input Arguments

ADS — Audio datastore

audioDatastore object

Specify ADS as an audioDatastore object.

parmode — Option to read data in parallel

"off" (default) | "auto" | "on"

Option to read data in parallel, specified as one of these values:

• "off" — Run in serial on the MATLAB^® client.

• "auto" — Use a parallel pool if one is open or if MATLAB can automatically create one. If a parallel pool is not available, run in serial on the MATLAB client.

• "on" — Use a parallel pool if one is open or if MATLAB can automatically create one. If a parallel pool is not available, throw an error.

If you do not have a parallel pool open and automatic pool creation is enabled, MATLAB opens a pool using the default cluster profile. To use a parallel pool to run computations in MATLAB, you must have Parallel Computing Toolbox. For more information, see Run MATLAB Functions with Automatic Parallel Support (Parallel Computing Toolbox).

Before R2026b: To run in parallel, set UseParallel to true (1).

Example: readall(ds,UseParallel="auto")

Data Types: char | string

Output Arguments

data — All audio files in audio datastore

cell array

All files in the audio datastore, returned as a cell array where each cell corresponds to a file.

Extended Capabilities

Automatic Parallel Support

Accelerate code by automatically running computation in parallel using Parallel Computing Toolbox™.

The readall function has automatic parallel support.

To run computations in parallel, set the parmode argument to "on" or "auto".

For more information, see Run MATLAB Functions with Automatic Parallel Support (Parallel Computing Toolbox).

Version History

Introduced in R2018b

R2026b: Enhanced control over parallel execution with UseParallel argument

The parmode argument now accepts "off", "auto", or "on" values instead of true or false. This change gives you more control over when to use a parallel pool for parallel execution.

Specifying the UseParallel argument as true or false is not recommended.

This table shows how to update your code depending on your goal.

Goal	Not recommended	Recommended
Write code that runs on the MATLAB client.	readall(ADS, UseParallel=false)	readall(ADS, UseParallel="off")
Write portable code that runs on a parallel pool and, if a pool is not available, runs on the MATLAB client.	readall(ADS, UseParallel=true)	readall(ADS, UseParallel="auto")
Write code that runs on a parallel pool and errors if a pool is not available.	N/A	readall(ADS, UseParallel="on")