How to obtain public key from a secret key?

[devashishdxt]

I'm not able to find any way to get public key corresponding to any secret key. Is there a way to obtain it?

[tarcieri]

The relevant mathematical function is fixed-base scalar multiplication.

This project contains a crate-per-elliptic curve, and none of them implement scalar multiplication.

Thus I will leave this issue open, noting @str4d has in fact contributed an immaculately written field arithmetic backend for the NIST P-256 elliptic curve, with the caveat that he purposefully was trying to solve the specific problems of point compression and decompression.

[tarcieri]

The p256 and k256 crates now both support scalar multiplication.

The next steps here, I think, are to define traits which generically provide access to fixed-base scalar multiplication.

I opened an issue about that here: #22

[tarcieri]

This was fixed in #49.

When the arithmetic backend is enabled for a particular curve, PublicKey::from_secret_key is available.

I might do some refactoring to change that to SecretKey::compressed_public_key() and SecretKey::uncompressed_public_key().