I'm sorry but i don't understand, can you give me an example
I do not have the necessary bases in mathematics and you lost me with "constant is c" & d

ideally a small python script would be welcome but I'm certainly asking too much

Signed: the noob ^^
i think you should start at the basics and read what Elliptic Curve Cryptography and Modular Arithmetic are before trying to come up with the code that computes half of a public key!