Discrete log in quotient rings of univariate polynomial rings
I'm quite noob with sage and math in general. It'd be epic if someone could give some guidance!
I've come across a problem that needs to compute some discrete logs for elements in something like
PolynomialRing(GF(p)).quotient(some_polynomial)
I didn't find functions at quotient polynomial ring sage docs to compute it, but I suspect it's possible to do it with Pohlig-Hellman. Is there already existing functionality in sage that helps me compute this?
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In general, a quotient of the shape Fp[x]/(f) is a field for a fixed, irreducible polynomial f. Let n be its degree. Up to isomorphism, there is "exactly one field" with q=pn elements. We may denote it by Fq. (But it is practically in sage also constructed in the same manner for an other polynomial. Well, i need a handy notation. In fact, sage can take f as
modulusdirectly.) So Fp/(f)≅Fq. The structure of the multiplicative group (F×q,⋅) of invertible (i.e. non-zero) elements in this field is known. It is a group of order (q−1) with one generator. We can ask sage to give us a generator. Now, in practice, we need to know something explicitly, in order to solve something explicitly, please provide explicit data.