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This example shows how to populate a 1-D
Lookup Table block using the parameter dialog box. The lookup
table in this example approximates the function * y* =

`[-3, 3]`

.Copy a 1-D Lookup Table block from the Lookup Tables block library to a Simulink

^{®}model.In the 1-D Lookup Table block dialog box, enter the table dimensions and table data in the specified fields of the dialog box:

Set

**Number of table dimensions**to`1`

.Set

**Table data**to`[-27 -8 -1 0 1 8 27]`

.

Alternatively, to use an existing an existing lookup table (

`Simulink.LookupTable`

) object, select**Data specification**>**Lookup table object**.Enter the breakpoint data set using either of two methods:

To specify evenly spaced data points, set

**Breakpoint specification**to`Even spacing`

. Set**First point**to`-3`

and**Spacing**to`1`

. The block calculates the number of evenly spaced breakpoints based on the table data.To specify breakpoint data explicitly, set

**Breakpoint specification**to`Explicit values`

and set**Breakpoints 1**to`[-3:3]`

.

Use the following procedure to populate a 2-D Lookup Table block using the Lookup
Table Editor. In this example, the lookup table approximates the function * z* =

```
x
= [0, 2]
```

and ```
y
= [0, 2]
```

.Copy a 2-D Lookup Table block from the Lookup Tables block library to a Simulink model.

Open the Lookup Table Editor by selecting

**Lookup Table Editor**from the Simulink**Edit**menu or by clicking**Edit table and breakpoints**on the dialog box of the 2-D Lookup Table block.Under

**Viewing "n-D Lookup Table" block data**, enter the breakpoint data sets and table data in the appropriate cells. To change data, click a cell, enter the new value, and press**Enter**.In the cells associated with the

**Row Breakpoints**, enter each of the values`[0 1 2]`

.In the cells associated with the

**Column Breakpoints**, enter each of the values`[0 1 2]`

.In the table data cells, enter the values in the array

`[0 1 4; 1 2 5; 4 5 8]`

.

The Lookup Table Editor looks like this:

In the Lookup Table Editor, select

**File**>**Update Block Data**to update the data in the 2-D Lookup Table block.Close the Lookup Table Editor.

Use the following procedure to populate a Lookup Table Dynamic block using that
block's inports. In this example, the lookup table approximates the
function * y* = 3

`[0, 10]`

.Copy a Lookup Table Dynamic block from the Lookup Tables block library to a Simulink model.

Copy the blocks needed to implement the equation

= 3*y**x*^{2}to the Simulink model:One Constant block to define the input range, from the Sources library

One Math Function block to square the input range, from the Math Operations library

One Gain block to multiply the signal by 3, also from the Math Operations library

Assign the following parameter values to the Constant, Math Function, and Gain blocks using their dialog boxes:

Block Parameter Value Constant **Constant value**`0:10`

Math Function **Function**`square`

Gain **Gain**`3`

Input the breakpoint data set to the Lookup Table Dynamic block by connecting the outport of the Constant block to the inport of the Lookup Table Dynamic block labeled

**xdat**. This signal is the input breakpoint data set for.*x*Input the table data to the Lookup Table Dynamic block by branching the output signal from the Constant block and connecting it to the Math Function block. Then connect the Math Function block to the Gain block. Finally, connect the Gain block to the inport of the Lookup Table Dynamic block labeled

**ydat**. This signal is the table data for.*y*

Lookup Table Dynamic | n-D Lookup Table

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