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1D Look-Up Table

Purpose

Output an approximated one-dimensional function using intrapolation/extrapolation.

Library

Control / Functions & Tables

Description

pict

The 1D Look-Up Table block maps an input signal to an output signal. You define the mapping function by specifying a vector of input values and a vector of output values. If the input signal lies within the range of the input vector, the output value is calculated by linear interpolation between the appropriate two points. If the input signal is out of bounds, the block extrapolates using the first or last two points.

Step transitions are achieved by repeating an input value with different output values. If the input signal exactly matches the input value of such a discontinuity, the output signal will be the output value of the mapping function that is first encountered when moving away from the origin. If the discontinuity is at input value 0, the output signal will be the average of the two output values. This behavior can be overridden by defining three output values for the same input value; in this case the middle output value will be chosen.

Use the 2D Look-Up Table block to map two input signals to an output signal.

Parameters

Vector of input values x
The vector of input values x  . This vector must be the same size as the output vector and monotonically increasing. It should not contain more than three identical values.
Vector of output values f(x)
The vector containing the output values f(x)  . This vector must be the same size as the input vector.

Probe Signals

Input
The block input signal.
Output
The block output signal.