Use blocks from the Lookup Tables library to model nonlinearity. Lookup table blocks use arrays of data to map input values to output values, approximating mathematical functions. To approximate a function in N variables, use the n-D Lookup Table block:
1-D Lookup Table | Approximate one-dimensional function |
2-D Lookup Table | Approximate two-dimensional function |
Direct Lookup Table (n-D) | Index into n-dimensional table to retrieve element, vector, or 2-D matrix |
Interpolation Using Prelookup | Use precalculated index and fraction values to accelerate approximation of N-dimensional function |
Lookup Table Dynamic | Approximate a one-dimensional function using dynamic table |
Prelookup | Compute index and fraction for Interpolation Using Prelookup block |
Sine, Cosine | Implement fixed-point sine or cosine wave using lookup table approach that exploits quarter wave symmetry |
n-D Lookup Table | Approximate n-dimensional function |
Enter Breakpoints and Table Data
How to specify breakpoint data sets and table data for lookup table blocks
How to change the elements of lookup tables
Import Lookup Table Data from MATLAB
You can import table and breakpoint data from variables in the MATLAB workspace by referencing them in the Table and Breakpoints tab of the dialog box.
Import Lookup Table Data from Excel
This example shows how to use the MATLAB xlsread
function in a Simulink model to import data into a lookup
table.
Create a Logarithm Lookup Table
Example demonstrating how to work with lookup table blocks
Prelookup and Interpolation Blocks
Provides examples of using Prelookup and Interpolation Using Prelookup blocks together
Row-Major Algorithm in Existing Models Containing Lookup Table Blocks
Process for updating existing models to use row-major layout
Update Lookup Table Blocks to New Versions
Process for updating existing models to use current versions of lookup table blocks
Brief overview of lookup table blocks
Introduces the components of a lookup table
Describes the various blocks in the Lookup Tables library
Guidelines for Choosing a Lookup Table
How to select the best lookup table for your application
Characteristics of Lookup Table Data
Describes requirements of lookup table data and outlines how to represent discontinuous data
Methods for Approximating Function Values
How to set the method by which lookup table blocks approximate function values
Optimize Generated Code for Lookup Table Blocks
Provides tips for optimizing generated code for lookup table blocks