Export FIS and Simulation Data from Fuzzy Logic Designer

Since R2022b

Once you design or tune your FIS using Fuzzy Logic Designer, you can export the active and stored designs to:

The MATLAB^® workspace
FIS files (*.fis)
MAT files (*.mat)

You can also export simulation results for your FIS designs.

Export FIS to Workspace

To export a FIS design to the MATLAB workspace, in Fuzzy Logic Designer, select Export > Export Fuzzy Inference System to Workspace.

App toolstrip showing the Export Fuzzy Inference System to Workspace selection in the Export drop-down menu on the far right side of the toolstrip.

The Export Fuzzy Inference System to Workspace dialog box lists the active FIS design along with any stored designs.

Export Fuzzy Inference Systems to Workspace dialog box containing a table with FIS designs

In the Export column, select one or more systems that you want to export.

The active FIS design is selected by default. (since R2024a)

In the Export As column, specify names for the workspace variables.

Click Export.

The app saves the FIS to the MATLAB workspace as one of the following types of objects.

mamfis — Type-1 Mamdani FIS
sugfis — Type-1 Sugeno FIS
mamfistype2 — Type-2 Mamdani FIS
sugfistype2 — Type-2 Sugeno FIS

Once you export your FIS, you can:

Perform additional simulations at the command line using the evalfis function.
Simulate your system in Simulink^® using the Fuzzy Logic Controller block.
Generate code for your system. For more information, see Deployment.

Save FIS to File

To save your FIS to a file, in Fuzzy Logic Designer, under Save, select the fuzzy inference system.

You can select the current active design or any of the stored designs.

App toolstrip showing the Save drop-down menu. The cursor is pointing to the single FIS listed in the drop-down menu.

In the Save Fuzzy Inference System dialog box, specify a filename and location, and click Save.

When saving a FIS design, you can use a FIS file or a MAT file.
When saving a FIS tree design, you must use a MAT file.

Export Simulation Data

After evaluating your FIS using Fuzzy Logic Designer, you can export the following simulation results to the MATLAB workspace for the active and stored designs.

Control surface data points
Rule inference data (individual FIS only)
Error distribution data (since R2023a)
System validation data (since R2023a)
FIS tree data flow results (FIS tree only) (since R2024a)

In Fuzzy Logic Designer, select Export > Export Simulation Results to Workspace.

App toolstrip showing the Export Simulation Results to Workspace selection in the Export drop-down menu on the far right side of the toolstrip.

The Export Simulation Results to Workspace dialog box lists the simulation results that are available for export. To export simulation results, you must first view the corresponding simulation document in the app.

The following figure shows the Export Simulation Results to Workspace dialog box for a single FIS object.

Export Simulation Results to Workspace dialog box

The Simulation Results column indicates the FIS designs and the type of simulation data using one of the following entries, where <design> indicates the FIS design.

<design>_ControlSurfaceData — Control surface data points
<design>_RuleInferenceData — Rule inference data
<design>_ErrorDistributionData — Error distribution data
SystemValidationData — System validation data for all selected designs
<design>_FISTreeDataFlowData — FIS tree data flow results

In the Export column, select one or more simulation results that you want to export.

In the Export As column, specify names for the workspace variables.

Click Export.

The app saves each selected simulation result to the MATLAB workspace as a structure, as defined in the following table.

Simulation Data	Description
Control surface data points	Data points for the most recent plot displayed in the Control Surface document for the active design, exported as a structure with the following fields. `X` — Data values for first selected input `Y` — Data values for second selected input `Z` — Data values for selected output The dimensions of `X`, `Y`, and `Z` match the Mesh Points selections in the Control Surface document. This control surface data matches the data points generated by the `gensurf` function.
Rule inference data	Rule inference results for the active design, including intermediate computed values, exported as a structure with the following fields. `inputs` — Input values. `numSamplePoints` — Number of sample points in output fuzzy sets. To specify this value, on the Design tab, set the Number of Samples parameter. `outputs` — Output values. `fuzzifiedInputs` — Fuzzified input values. `ruleOutputs` — Rule outputs calculated by applying the rule firing strengths to the output membership function using the FIS implication method. `aggregatedOutputs` — Aggregated output calculated by combining the rule outputs using the FIS aggregation method. `rulefiringStrengths` — Rule firing strengths calculated by applying the rule connection operator to the values of the fuzzified inputs. The dimensions of the `fuzzifiedInputs`, `ruleOutputs`, `aggregatedOutputs`, and `rulefiringStrengths` fields depend on the type of FIS you exported. For more information, see `evalfis`.
Error distribution data (since R2023a)	Error distribution data for the active design, exported as a structure with the following fields, each containing a numeric array. `refInput` — Validation input data specified on the Design tab, in the Input Data drop-down list `refOutput` — Validation input data specified on the Design tab, in the Output Data drop-down list `simOutput` — FIS outputs from processing the values in `refInput` `simError` — Simulation error, which is the difference between the values in `refOutput` and `simOutput`
System validation data (since R2023a)	System validation data for all selected FIS designs, exported as a structure with the following fields. `refInput` — Validation input data specified on the Design tab, in the Input Data drop-down list `refOutput` — Validation input data specified on the Design tab, in the Output Data drop-down list `simOutput` — FIS outputs from processing the values in `refInput`, returned as a structure with one field for each selected FIS design `simError` — Simulation error, which is the difference between the values in `refOutput` and `simOutput`, returned as a structure with one field for each selected FIS design A selected design is a design for which you select the Compare option in the Design Browser.
FIS tree data flow results (since R2024a)	FIS tree data propagation for the active design using the most recent input values specified in the FIS Tree Plot document, exported as a structure with the following fields. `fisTree` — Input and output data for the overall FIS tree, returned as a structure with `input` and `output` fields, respectively. `fis` — Input and output data for each component FIS in the FIS tree, returned as a structure array with `input` and `output` fields, respectively.

For the active FIS design, the exported simulation results correspond to the simulation settings, such as the input values in the Rule Inference document or the selected axes in the Control Surface document, currently defined in the app.

For a stored FIS design, the exported simulation results correspond to the simulation settings when the design was most recently active in the app. In other words, the exported results for a stored design may not use the simulation settings currently defined in the app.