# RegressionSVM Predict

Predict responses using support vector machine (SVM) regression model

• Library:
• Statistics and Machine Learning Toolbox / Regression

## Description

The RegressionSVM Predict block predicts responses using an SVM regression object (`RegressionSVM` or `CompactRegressionSVM`).

Import a trained SVM regression object into the block by specifying the name of a workspace variable that contains the object. The input port x receives an observation (predictor data), and the output port yfit returns a predicted response for the observation.

## Ports

### Input

expand all

Predictor data, specified as a column vector or row vector of one observation.

#### Dependencies

• The variables in x must have the same order as the predictor variables that trained the SVM model specified by ```Select trained machine learning model```.

• If you set `'Standardize',true` in `fitrsvm` when training the SVM model, then the RegressionSVM Predict block standardizes the values of x using the means and standard deviations in the `Mu` and `Sigma` properties (respectively) of the SVM model.

Data Types: `single` | `double` | `half` | `int8` | `int16` | `int32` | `int64` | `uint8` | `uint16` | `uint32` | `uint64` | `Boolean` | `fixed point`

### Output

expand all

Predicted response, returned as a scalar.

Data Types: `single` | `double` | `half` | `int8` | `int16` | `int32` | `int64` | `uint8` | `uint16` | `uint32` | `uint64` | `Boolean` | `fixed point`

## Parameters

expand all

### Main

Specify the name of a workspace variable that contains a `RegressionSVM` object or `CompactRegressionSVM` object.

When you train the SVM model by using `fitrsvm`, the following restrictions apply:

• The predictor data cannot include categorical predictors (`logical`, `categorical`, `char`, `string`, or `cell`). If you supply training data in a table, the predictors must be numeric (`double` or `single`). Also, you cannot use the `'CategoricalPredictors'` name-value argument. To include categorical predictors in a model, preprocess the categorical predictors by using `dummyvar` before fitting the model.

• The value of the `'ResponseTransform'` name-value argument must be `'none'` (default).

• The value of the `'KernelFunction'` name-value argument must be `'gaussian'`, `'linear'` (default), or `'polynomial'`.

#### Programmatic Use

 Block Parameter: `TrainedLearner` Type: workspace variable Values: `RegressionSVM` object | `CompactRegressionSVM` object Default: `'svmMdl'`

### Data Types

Fixed-Point Operational Parameters

Specify the rounding mode for fixed-point operations. For more information, see Rounding (Fixed-Point Designer).

Block parameters always round to the nearest representable value. To control the rounding of a block parameter, enter an expression using a MATLAB® rounding function into the mask field.

#### Programmatic Use

 Block Parameter: `RndMeth` Type: character vector Values: ```'Ceiling' | 'Convergent' | 'Floor' | 'Nearest' | 'Round' | 'Simplest' | 'Zero'``` Default: `'Floor'`

Specify whether overflows saturate or wrap.

ActionRationaleImpact on OverflowsExample

Select this check box (`on`).

Your model has possible overflow, and you want explicit saturation protection in the generated code.

Overflows saturate to either the minimum or maximum value that the data type can represent.

The maximum value that the `int8` (signed 8-bit integer) data type can represent is 127. Any block operation result greater than this maximum value causes overflow of the 8-bit integer. With the check box selected, the block output saturates at 127. Similarly, the block output saturates at a minimum output value of –128.

Clear this check box (`off`).

You want to optimize efficiency of your generated code.

You want to avoid overspecifying how a block handles out-of-range signals. For more information, see Troubleshoot Signal Range Errors (Simulink).

Overflows wrap to the appropriate value that the data type can represent.

The maximum value that the `int8` (signed 8-bit integer) data type can represent is 127. Any block operation result greater than this maximum value causes overflow of the 8-bit integer. With the check box cleared, the software interprets the overflow causing value as `int8`, which can produce an unintended result. For example, a block result of 130 (binary 1000 0010) expressed as `int8` is –126.

#### Programmatic Use

 Block Parameter: `SaturateOnIntegerOverflow` Type: character vector Values: `'off' | 'on'` Default: `'off'`

Select this parameter to prevent the fixed-point tools from overriding the data type you specify for the block. For more information, see Use Lock Output Data Type Setting (Fixed-Point Designer).

#### Programmatic Use

 Block Parameter: `LockScale` Type: character vector Values: `'off' | 'on'` Default: `'off'`
Data Type

Specify the data type for the yfit output. The type can be inherited, specified directly, or expressed as a data type object such as `Simulink.NumericType`.

When you select `Inherit: auto`, the block uses a rule that inherits a data type.

Click the button to display the Data Type Assistant, which helps you set the data type attributes. For more information, see Specify Data Types Using Data Type Assistant (Simulink).

#### Programmatic Use

 Block Parameter: `OutDataTypeStr` Type: character vector Values: `'Inherit: auto'` | `'double'` | `'single'` | `'half'` | `'int8'` | `'uint8'` | `'int16'` | `'uint16'` | `'int32'` | `'uint32'` | `'int64'` | `'uint64'` | `'boolean'` | `'fixdt(1,16)'` | `'fixdt(1,16,0)'` | `'fixdt(1,16,2^0,0)'` | ```''``` Default: `'Inherit: auto'`

Lower value of the yfit output range that Simulink® checks.

Simulink uses the minimum value to perform:

Note

The Output minimum parameter does not saturate or clip the actual yfit signal. Use the Saturation (Simulink) block instead.

#### Programmatic Use

 Block Parameter: `OutMin` Type: character vector Values: `'[]'` | scalar Default: `'[]'`

Upper value of the yfit output range that Simulink checks.

Simulink uses the maximum value to perform:

Note

The Output maximum parameter does not saturate or clip the actual yfit signal. Use the Saturation (Simulink) block instead.

#### Programmatic Use

 Block Parameter: `OutMax` Type: character vector Values: `'[]'` | scalar Default: `'[]'`

Specify the data type of a parameter for kernel computation. The type can be specified directly or expressed as a data type object such as `Simulink.NumericType`.

The Kernel data type parameter specifies the data type of a different parameter depending on the type of kernel function of the specified SVM model. You specify the `'KernelFunction'` name-value argument when training the SVM model.

`'KernelFunction'` valueData Type
`'gaussian'` or `'rbf'`Kernel data type specifies the data type of the squared distance ${D}^{2}={‖x-s‖}^{2}$ for the Gaussian kernel $G\left(x,s\right)=\mathrm{exp}\left(-{D}^{2}\right)$, where x is the predictor data for an observation and s is a support vector.
`'linear'`Kernel data type specifies the data type for the output of the linear kernel function $G\left(x,s\right)=xs\text{'}$, where x is the predictor data for an observation and s is a support vector.
`'polynomial'`Kernel data type specifies the data type for the output of the polynomial kernel function $G\left(x,s\right)={\left(1+xs\text{'}\right)}^{p}$, where x is the predictor data for an observation, s is a support vector, and p is a polynomial kernel function order.

Click the button to display the Data Type Assistant, which helps you set the data type attributes. For more information, see Specify Data Types Using Data Type Assistant (Simulink).

#### Programmatic Use

 Block Parameter: `KernelDataTypeStr` Type: character vector Values: `'double'` | `'single'` | `'half'` | `'int8'` | `'uint8'` | `'int16'` | `'uint16'` | `'int32'` | `'uint32'` | `'uint64'` | `'int64'` | `'boolean'` | `'fixdt(1,16)'` | `'fixdt(1,16,0)'` | `'fixdt(1,16,2^0,0)'` | `''` Default: `'double'`

Lower value of the kernel computation internal variable range that Simulink checks.

Simulink uses the minimum value to perform:

Note

The Kernel minimum parameter does not saturate or clip the actual kernel computation value signal.

#### Programmatic Use

 Block Parameter: `KernelOutMin` Type: character vector Values: `'[]'` | scalar Default: `'[]'`

Upper value of the kernel computation internal variable range that Simulink checks.

Simulink uses the maximum value to perform:

Note

The Kernel maximum parameter does not saturate or clip the actual kernel computation value signal.

#### Programmatic Use

 Block Parameter: `KernelOutMax` Type: character vector Values: `'[]'` | scalar Default: `'[]'`

## Block Characteristics

 Data Types `Boolean` | `double` | `fixed point` | `half` | `integer` | `single` Direct Feedthrough `yes` Multidimensional Signals `no` Variable-Size Signals `no` Zero-Crossing Detection `no`

## Tips

• If you are using a linear SVM model and it has many support vectors, then prediction can be slow. To efficiently predict responses based on a linear SVM model, remove the support vectors from the `RegressionSVM` or `CompactRegressionSVM` object by using `discardSupportVectors`.

## Alternative Functionality

You can use a MATLAB Function block with the `predict` object function of an SVM regression object (`RegressionSVM` or `CompactRegressionSVM`). For an example, see Predict Class Labels Using MATLAB Function Block.

When deciding whether to use the RegressionSVM Predict block in the Statistics and Machine Learning Toolbox™ library or a MATLAB Function block with the `predict` function, consider the following:

• If you use the Statistics and Machine Learning Toolbox library block, you can use the Fixed-Point Tool (Fixed-Point Designer) to convert a floating-point model to fixed point.

• Support for variable-size arrays must be enabled for a MATLAB Function block with the `predict` function.

• If you use a MATLAB Function block, you can use MATLAB functions for preprocessing or post-processing before or after predictions in the same MATLAB Function block.

## Compatibility Considerations

expand all

Behavior changed in R2021a

## Extended Capabilities

### Functions

Introduced in R2020b