# encodeOptimizer(_:) Encodes an estimator optimizer. ``` mutating func encodeOptimizer(_ value: T) throws where T : Encodable ``` ## Discussion Optimizers are used when fitting an estimator and usually contain state information such as momentum. This method encodes the optimizer state separately from model parameters. --- 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)