# update(_:withPreprocessed:eventHandler:) Updates a transformer with a new sequence of preprocessed features. ``` func update(_ transformer: inout PreprocessingUpdatableSupervisedEstimator.Transformer, withPreprocessed preprocessed: InputSequence, eventHandler: EventHandler? = nil) async throws where InputSequence : Sequence, InputSequence.Element == AnnotatedFeature ``` ## Parameters `transformer` A transformer to update. `preprocessed` A sequence of preprocessed features. `eventHandler` An event handler. --- Copyright © 2026 Apple Inc. All rights reserved. | [Terms of Use](https://www.apple.com/legal/internet-services/terms/site.html) | [Privacy Policy](https://www.apple.com/privacy/privacy-policy)