Instance Property
parity
The parity of the aggregate public key’s Y coordinate, as returned by secp256k1_xonly_pubkey_from_pubkey; used in Taproot tweak verification.
- iOS 13.0+
- macCatalyst 13.0+
- macOS 10.15+
- tvOS 13.0+
- visionOS 1.0+
- watchOS 6.0+
var parity: Bool { get }
Discussion
true = odd Y, false = even Y. BIP-340 signatures are verified against the even-Y representative of a point, so the parity bit is tracked separately and consulted during tweak verification (secp256k1_musig_pubkey_xonly_tweak_add_check) and the Taproot output-key derivation (secp256k1_xonly_pubkey_tweak_add_check).