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replace

Replace all Lookup Table blocks with compressed lookup tables

Since R2020a

Description

example

replace(compressionResult) replaces all n-D Lookup Table blocks in a system with the compressed versions described in the LUTCompressionResult object compressionResult.

example

replace(compressionResult, index) replaces the lookup tables at the indices specified by index.

Examples

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This example shows how to compress all Lookup Table blocks in a system.

Open the model containing the lookup tables that you want to compress.

system = 'sldemo_fuelsys';
open_system(system)

Use the FunctionApproximation.compressLookupTables function to compress all of the lookup tables in the model. The output returns all blocks that are modified and the memory savings for each.

compressionResult = FunctionApproximation.compressLookupTables(system)
- Found 5 supported lookup tables
- Percent reduction in memory for compressed solution
	-  2.37% for sldemo_fuelsys/fuel_rate_control/airflow_calc/Pumping Constant
	-  2.37% for sldemo_fuelsys/fuel_rate_control/control_logic/Throttle.throttle_estimate/Throttle Estimation
	-  3.55% for sldemo_fuelsys/fuel_rate_control/control_logic/Speed.speed_estimate/Speed Estimation
	-  6.38% for sldemo_fuelsys/fuel_rate_control/control_logic/Pressure.map_estimate/Pressure Estimation
	-  9.38% for sldemo_fuelsys/fuel_rate_control/airflow_calc/Ramp Rate Ki

compressionResult = 

  LUTCompressionResult with properties:

                  MemoryUnits: bytes
             MemoryUsageTable: [5x5 table]
                 NumLUTsFound: 5
              NumImprovements: 5
              TotalMemoryUsed: 6024
           TotalMemoryUsedNew: 5796
           TotalMemorySavings: 228
    TotalMemorySavingsPercent: 3.7849
                          SUD: 'sldemo_fuelsys'
                  WordLengths: [8 16 32]
                  FindOptions: [1x1 Simulink.internal.FindOptions]
                      Display: 1

Use the replace function to replace each Lookup Table block with a block containing the original and compressed version of the lookup table.

replace(compressionResult);

You can revert the lookup tables back to their original state using the revert function.

revert(compressionResult);

Input Arguments

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Results of lookup table compression, specified as a LUTCompressionResult object.

Index of the Lookup Table blocks to replace in the system, specified as an integer-valued scalar or vector.

The index of each lookup table corresponds to the ID column in the MemoryUsageTable property of the LUTCompressionResult object.

Data Types: double

Version History

Introduced in R2020a