You should read BIP-143, all the information you seek is explained there.
In other words, I'm trying to calculate the K point.
If by "K" you mean the corresponding point of the ephemeral key used in signing referred to "k" in some standards, then you can't do that. The whole security of ECDSA relies on the fact that this is impossible to compute.I'm not looking for the private k value
I want to calculate the K point which is public.
in pubkey and pubkeyhash type signatures
N = 115792089237316195423570985008687907852837564279074904382605163141518161494337
type (X) = EllipticCurve Point on x ^ 3 + 7 for PrimeFileld
type (G) = EllipticCurve Base Point on x ^ 3 + 7 for PrimeFileld
type (R) = (max 256-bit) Integer
type (S) = (max 256-bit) Integer
type (Z) = (max 256-bit) Integer
(How to calculate K on EllipticCurve): retrun EcPoint
(R / S% N) * X + (Z / S% N) * G
This gives us the point K on the Elliptic Curve
If K.x == R
signature is correct.
Alice Signed. How does Bob understand this. Somehow it has to calculate the message (Z value) so that it can check the signature.
My question is I'm trying to figure out how Bob calculates this on my Z value. Not calculating K. If I wanted to find the equivalent of point K in positive numbers, I would be interested in ECDLP. But our topic is not ECDLP. Thanks.
