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# gensurf

Generate Fuzzy Inference System output surface

## Syntax

gensurf(fis)
gensurf(fis,inputs,output)
gensurf(fis,inputs,output,grids)
gensurf(fis,inputs,output,grids,refinput)
gensurf(fis,inputs,output,grids,refinput,numofpoints)
[x,y,z]=gensurf(...)

## Description

gensurf(fis) generates a plot of the output surface of a given fuzzy inference system (fis) using the first two inputs and the first output.

gensurf(fis,inputs,output) generates a plot using the inputs (one or two) and output (only one is allowed) given, respectively, by the vector, inputs, and the scalar, output.

gensurf(fis,inputs,output,grids) allows you to specify the number of grids in the X (first, horizontal) and Y (second, vertical) directions. If grids is a two element vector, you can set the grids in the X and Y directions independently.

gensurf(fis,inputs,output,grids,refinput) allows you to specify a reference input, and can be used if there are more than two outputs. The length of the vector refinput is the same as the number of inputs:

• Enter NaNs for the entries of refinput corresponding to the inputs whose surface is being displayed.

• Enter real double scalars to fix the values of other inputs.

gensurf(fis,inputs,output,grids,refinput,numofpoints) allows you to specify the number of sample points on which to evaluate the membership functions in the input or output range. If numofpoints is not specified, a default value of 101 is used.

[x,y,z]=gensurf(...) returns the variables that define the output surface and suppresses automatic plotting.

## Examples

```a = readfis('tipper');
gensurf(a)
```

```a = gensurf(Temp,[1 2],1,[20 20],[nan nan 0.2]);
```

This equation generates the surface of a three-input FIS named Temp from its first two inputs to its first output, while fixing a reference value for the third input at .2.

## See Also

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