On: Lattices vs. Cranks

Hm, does this kind of approach also work for the "recover the algebraic expression that generated an approximated float" problem?

If by "this kind of approach" you mean lattice tools, then I think the answer is yes. See the link below for an example in the Wikipedia page on the LLL. Also the second link may be helpful

https://en.wikipedia.org/wiki/Lenstra%E2%80%93Lenstra%E2%80%...

https://eprint.iacr.org/2023/032.pdf