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# MLProgress.Metric

Metrics you use to evaluate a model’s performance during a training
session.

```
enum Metric
```

## Topics

### Retrieving metric keys

[`case accuracy`](/documentation/CreateML/MLProgress/Metric/accuracy)

The metric for the model’s accuracy.

[`case contentLoss`](/documentation/CreateML/MLProgress/Metric/contentLoss)

The metric for the style transfer model’s content loss.

[`case loss`](/documentation/CreateML/MLProgress/Metric/loss)

The metric for the model’s loss.

[`case maximumError`](/documentation/CreateML/MLProgress/Metric/maximumError)

The metric for the model’s maximum error.

[`case rootMeanSquaredError`](/documentation/CreateML/MLProgress/Metric/rootMeanSquaredError)

The metric for the model’s root mean squared error (RMSE).

[`case styleLoss`](/documentation/CreateML/MLProgress/Metric/styleLoss)

The metric for the style transfer model’s style loss.

[`case stylizedImageURL`](/documentation/CreateML/MLProgress/Metric/stylizedImageURL)

The location of the stylized image content in the file system.

[`case validationAccuracy`](/documentation/CreateML/MLProgress/Metric/validationAccuracy)

The metric for the model’s validation accuracy.

[`case validationLoss`](/documentation/CreateML/MLProgress/Metric/validationLoss)

The metric for the model’s validation loss.

[`case validationMaximumError`](/documentation/CreateML/MLProgress/Metric/validationMaximumError)

The metric for the model’s validation maximum error.

[`case validationRootMeanSquaredError`](/documentation/CreateML/MLProgress/Metric/validationRootMeanSquaredError)

The metric for the model’s validation root mean squared error (RMSE).

## Relationships

### Conforms To

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

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

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

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

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

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

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

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

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

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

---

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