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copyFileFromStore

Copy files from FileStore object to local file system

Since R2022a

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Syntax

copyFileFromStore(store,keySet,fileSet)

Description

example

copyFileFromStore(store,keySet,fileSet) copies files from store as specified by the keys keySet to the local file system fileSet.

Examples

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Open Live Script

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. Copy files from this object as specified by their corresponding keys using the copyFileFromStore function.

The following simulation finds the average and standard deviation of random matrices and stores the results in the FileStore object.

type workerStatsCode
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. 

store = pool.FileStore;

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.

keys(store)
ans = 4×1 string
    "result_1"
    "result_2"
    "result_3"
    "result_4"

Copy files from the file storage as specified by the corresponding keys "result_1" and "result_2" to the local files "run_1.mat" and "run_2.mat".

copyFileFromStore(store,["result_1" "result_2"],["run_1.mat" "run_2.mat"])

Display all the information on the variables stored in the local files.

whos -file 'run_1.mat'
  Name      Size            Bytes  Class     Attributes

  M         1x4                32  double              
  S         1x4                32  double              

whos -file 'run_2.mat'
  Name      Size            Bytes  Class     Attributes

  M         1x8                64  double              
  S         1x8                64  double

Input Arguments

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File storage shared by MATLAB clients and workers, specified as a FileStore object.

Keys to copy, specified as a character vector, string scalar, string array, or cell array of character vectors or strings. keySet and fileSet must have the same number of elements.

Example: ["myDataKey" "myLogKey"]

Local files, specified as a character vector, string scalar, string array, or cell array of character vectors or strings. keySet and fileSet must have the same number of elements.

Example: ["/data/run.mat" "/tmp/run_log.txt"]

Version History

Introduced in R2022a

See Also

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