2D Look-Up Table

Purpose

Compute piece-wise linear function of two input signals

Library

Control / Functions & Tables

Description

../../_images/lookup2d.svg

The 2D Look-Up Table block maps two input signals to an output signal. You define the mapping function by specifying two vectors of input values and a matrix of output values. The input vector \(x\) corresponds to the rows of the output matrix, the input vector \(y\), to the columns.

The output value is interpolated or extrapolated from the block parameters using the technique described for the 1D Look-Up Table block.

Parameters

Vector of input values x

The vector of input values \(x\). This vector must be the same size as the number of rows in the output matrix and monotonically increasing. It should not contain more than three identical values.

Vector of input values y

The vector of input values \(y\). This vector must be the same size as the number of columns in the output matrix and monotonically increasing. It should not contain more than three identical values.

Matrix of output values f(x,y)

The matrix containing the output values \(f(x,y)\). The number of rows and columns must match the size of the input vectors.

Locate discontinuities

When set to on, the Look-Up Table defines zero-crossing signals that prevent a variable-step solver from inadvertently stepping over a discontinuity of the input-output mapping or its derivative.

When set to off, the Look-Up Table does not explicitly influence the steps taken by a variable-step solver.

Probe Signals

Input x

The block input signal \(x\).

Input y

The block input signal \(y\).

Output

The block output signal.