# init(seedRepresentation:publicKey:) Initializes a private key from a seed representation and optional public key. ``` init(seedRepresentation: D, publicKey: MLKEM1024.PublicKey?) throws where D : DataProtocol ``` ## Parameters `seedRepresentation` The seed representation `d||z`, as specified in the `ML-KEM.KeyGen_internal(d,z)` algorithm (Algorithm 16) of FIPS 203. `publicKey` An optional public key. Pass this to check that the initialized private key is consistent with the public key. The initializer throws if the public key doesn’t match the expected value. --- 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)