Download MATLAB SIMULINK 7 - DEVELOPING S-FUNCTIONS User`s guide

Fully Inlined S-Function with the mdlRTW Routine
• How to use the mdlRTW routine to customize the Real-Time Workshop
generated code to produce the optimal code for a given set of block
parameters
• How to generate an inlined TLC file for an S-function in a combination of the
fully-inlined form and/or the wrapper form
The Direct-Index Lookup Table Algorithm
The 1-D lookup table block provided in the Simulink library uses interpolation
or extrapolation when computing outputs. This extra accuracy is not needed in
all situations. In this example, you will create a lookup table that directly
indexes the output vector (y-data vector) based on the current input (x-data)
point.
This direct 1-D lookup example computes an approximate solution, p(x), to a
partially known function f(x) at x=x0, given data point pairs (x,y) in the form of
an x data vector and a y data vector. For a given data pair (e.g., the i'th pair),
y_i = f(x_i). It is assumed that the x-data values are monotonically increasing.
If x0 is outside of the range of the x-data vector, then the first or last point will
be returned.
The parameters to the S-function are:
XData, YData, XEvenlySpaced
XData and YData are double vectors of equal length representing the values of
the unknown function. XDataEvenlySpaced is a scalar, 0.0 for false and 1.0 for
true. If the XData vector is evenly spaced, then more efficient code is generated.
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