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# fitted(to:validateOn:eventHandler:)

Fits a transformer to a sequence of examples while validating with a validation sequence.

```
func fitted<Input, Validation>(to input: Input, validateOn validation: Validation, eventHandler: EventHandler?) async throws -> Self.Transformer where Input : Sequence, Validation : Sequence, Input.Element == AnnotatedFeature<Self.Transformer.Input, Self.Annotation>, Validation.Element == AnnotatedFeature<Self.Transformer.Input, Self.Annotation>
```

## Parameters

`input`

A sequence of examples used for fitting the transformer.

`validation`

A sequence of examples used for validating the fitted transformer.

`eventHandler`

An event handler.

## Return Value

The fitted transformer.

---

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