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# MLActivityClassifier.ModelParameters

Model training parameters that direct the training process for an
activity classifier model.

```
struct ModelParameters
```

## Topics

### Creating parameters

[`init(validation: MLActivityClassifier.ModelParameters.Validation, batchSize: Int?, maximumIterations: Int?, predictionWindowSize: Int?)`](/documentation/CreateML/MLActivityClassifier/ModelParameters-swift.struct/init(validation:batchSize:maximumIterations:predictionWindowSize:))

Creates a set of activity classifier parameters that includes a
validation dataset in a data source.

[`init(validationData:batchSize:maximumIterations:predictionWindowSize:)`](/documentation/CreateML/MLActivityClassifier/ModelParameters-swift.struct/init(validationData:batchSize:maximumIterations:predictionWindowSize:))

Creates a set of activity classifier parameters that includes a
validation dataset in a data source.

[`enum Validation`](/documentation/CreateML/MLActivityClassifier/ModelParameters-swift.struct/Validation-swift.enum)

The source of a validation dataset for an activity classifier.

### Accessing the training parameters

[`var validationData: MLDataTable?`](/documentation/CreateML/MLActivityClassifier/ModelParameters-swift.struct/validationData)

The activity classifier’s validation dataset.

[`var batchSize: Int?`](/documentation/CreateML/MLActivityClassifier/ModelParameters-swift.struct/batchSize)

The number of sequence chunks the training session uses per
iteration.

[`var maximumIterations: Int?`](/documentation/CreateML/MLActivityClassifier/ModelParameters-swift.struct/maximumIterations)

The maximum number of iterations over the training data the training
session uses.

[`var predictionWindowSize: Int?`](/documentation/CreateML/MLActivityClassifier/ModelParameters-swift.struct/predictionWindowSize)

The number of samples for each labeled activity.

[`var validation: MLActivityClassifier.ModelParameters.Validation`](/documentation/CreateML/MLActivityClassifier/ModelParameters-swift.struct/validation-swift.property)

The validation data source.

### Describing parameters

[`var description: String`](/documentation/CreateML/MLActivityClassifier/ModelParameters-swift.struct/description)

A text representation of the activity-model parameters.

[`var debugDescription: String`](/documentation/CreateML/MLActivityClassifier/ModelParameters-swift.struct/debugDescription)

A text representation of the activity-model parameters that’s suitable
for output during debugging.

[`var playgroundDescription: Any`](/documentation/CreateML/MLActivityClassifier/ModelParameters-swift.struct/playgroundDescription)

A description of the activity-model parameters shown in a playground.

### Default Implementations

[CustomDebugStringConvertible Implementations](/documentation/CreateML/MLActivityClassifier/ModelParameters-swift.struct/CustomDebugStringConvertible-Implementations)

[CustomPlaygroundDisplayConvertible Implementations](/documentation/CreateML/MLActivityClassifier/ModelParameters-swift.struct/CustomPlaygroundDisplayConvertible-Implementations)

[CustomStringConvertible Implementations](/documentation/CreateML/MLActivityClassifier/ModelParameters-swift.struct/CustomStringConvertible-Implementations)

## Relationships

### Conforms To

[`Escapable`](/documentation/Swift/Escapable)

[`Copyable`](/documentation/Swift/Copyable)

[`CustomStringConvertible`](/documentation/Swift/CustomStringConvertible)

[`CustomDebugStringConvertible`](/documentation/Swift/CustomDebugStringConvertible)

[`CustomPlaygroundDisplayConvertible`](/documentation/Swift/CustomPlaygroundDisplayConvertible)

---

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