Returns whether element a is totally real.
Returns whether the element a is totally positive, that is, totally real and with positive image in CC.
Given a CM algebra K, returns the unique totally real subalgebra, with an embedding.
Given an order S in a CM étale algebra A returns the groups of totally real units of S, as a subgroup of S * .
Given an order S in a CM étale algebra. Returns the groups of totally positive units of S, as a subgroup of S * .