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Simulink.data.dictionary.cleanupWorkerCache

Restore defaults after parallel simulation with data dictionary

Description

Simulink.data.dictionary.cleanupWorkerCache restores default settings after you have finished parallel simulation of a model that is linked to a data dictionary. Use this function in a spmd (Parallel Computing Toolbox) block, after you finish parallel simulation using parfor (Parallel Computing Toolbox) blocks, to restore default settings that were altered by the Simulink.data.dictionary.setupWorkerCache function.

During parallel simulation of a model that is linked to a data dictionary, you can allow each worker to access and modify the data in the dictionary independently of other workers. The function Simulink.data.dictionary.setupWorkerCache grants each worker a unique dictionary cache to allow independent access to the data, and the function Simulink.data.dictionary.cleanupWorkerCache restores cache settings to their default values.

You must have a Parallel Computing Toolbox™ license to perform parallel simulation using a parfor (Parallel Computing Toolbox) block.

Examples

Sweep Variant Control Using Parallel Simulation

To use parallel simulation to sweep a variant control (a Simulink.Parameter object whose value influences the variant condition of a Simulink.VariantExpression object) that you store in a data dictionary, use this code as a template. Change the names and values of the model, data dictionary, and variant control to match your application.

To sweep block parameter values or the values of workspace variables that you use to set block parameters, use Simulink.SimulationInput objects instead of the programmatic interface to the data dictionary. See Optimize, Estimate, and Sweep Block Parameter Values.

You must have a Parallel Computing Toolbox license to perform parallel simulation.

% For convenience, define names of model and data dictionary
model = 'mySweepMdl';
dd = 'mySweepDD.sldd';

% Define the sweeping values for the variant control
CtrlValues = [1 2 3 4];

% Grant each worker in the parallel pool an independent data dictionary 
% so they can use the data without interference
spmd 
    Simulink.data.dictionary.setupWorkerCache
end

% Determine the number of times to simulate
numberOfSims = length(CtrlValues);

% Prepare a nondistributed array to contain simulation output
simOut = cell(1,numberOfSims);

parfor index = 1:numberOfSims
    % Create objects to interact with dictionary data
    % You must create these objects for every iteration of the parfor-loop
    dictObj = Simulink.data.dictionary.open(dd);
    sectObj = getSection(dictObj,'Design Data');
    entryObj = getEntry(sectObj,'MODE'); 
    % Suppose MODE is a Simulink.Parameter object stored in the data dictionary
    
    % Modify the value of MODE
    temp = getValue(entryObj);
    temp.Value = CtrlValues(index);
    setValue(entryObj,temp);

    % Simulate and store simulation output in the nondistributed array
    simOut{index} = sim(model);
    
    % Each worker must discard all changes to the data dictionary and
    % close the dictionary when finished with an iteration of the parfor-loop
    discardChanges(dictObj);
    close(dictObj);
end

% Restore default settings that were changed by the function
% Simulink.data.dictionary.setupWorkerCache
% Prior to calling cleanupWorkerCache, close the model

spmd
    bdclose(model)
    Simulink.data.dictionary.cleanupWorkerCache
end

Note

If data dictionaries are open, you cannot use the command Simulink.data.dictionary.cleanupWorkerCache. To identify open data dictionaries, use Simulink.data.dictionary.getOpenDictionaryPaths.

Version History

Introduced in R2015a