keys - Return all keys of ValueStore or FileStore
object - MATLAB ([original](https://www.mathworks.com/help/parallel-computing/parallel.valuestore.keys.html)) ([raw](?raw))Main Content
Return all keys of ValueStore or FileStore object
Since R2022a
Syntax
Description
`keySet` = keys([store](#mw%5Fcdb1af86-d575-4ef0-9669-aeaf8df92ef0)) returns a string array containing all the keys in the ValueStore orFileStore object store.
Examples
Return Keys of ValueStore Object
Run a simulation on workers and retrieve the data storage of the job on a client. The data storage is a ValueStore object with key-value entries. Show the keys of this object.
The following simulation finds the inverse of random matrices and stores the results in the ValueStore object.
function workerInvCode(models) % Get the ValueStore of the current job store = getCurrentValueStore; for i = 1:numel(models) % Store simulation results in the ValueStore object pause(1); key = strcat("result_",num2str(i)); store(key) = inv(rand(models(i))); end end
Run a batch job on workers using the default cluster profile.
models = [4,8,32,20]; c = parcluster; job = batch(c,@workerInvCode,0,{models}); wait(job);
Retrieve the ValueStore object on the client.
Return a string array containing its keys.
keySet = 4×1 string "result_1" "result_2" "result_3" "result_4"
Return Keys of FileStore Object
Run a simulation on a parallel pool of process workers and retrieve the file storage on a client. The file storage is a FileStore object with key-file entries. Show the keys of this object.
The following simulation finds the average and standard deviation of random matrices and stores the results in the FileStore object.
function workerStatsCode(models) % Get the FileStore of the current job store = getCurrentFileStore; for i = 1:numel(models) % Compute the average and standard deviation of random matrices A = rand(models(i)); M = mean(A); S = std(A); % Save simulation results in temporary files sourceTempFile = strcat(tempname("C:\myTempFolder"),".mat"); save(sourceTempFile,"M","S"); % Copy files to FileStore object as key-file pairs key = strcat("result_",num2str(i)); copyFileToStore(store,sourceTempFile,key); end end
Start a parallel pool of process workers.
pool = parpool('Processes');
Starting parallel pool (parpool) using the 'Processes' profile ... Connected to the parallel pool (number of workers: 6).
Get the FileStore for this pool.
Run the simulation on the pool.
models = [4,8,32,20]; future = parfeval(@workerStatsCode,0,models); wait(future);
Show the keys of the FileStore object.
Input Arguments
store — Data or file storage shared by MATLAB® clients and workers
ValueStore object | FileStore object
Data or file storage shared by MATLAB clients and workers, specified as a ValueStore orFileStore object.
Version History
Introduced in R2022a