Function: bnrconductorofchar
Section: number_fields
C-Name: bnrconductorofchar
Prototype: GG
Help: bnrconductorofchar(bnr,chi): conductor of the character chi on the ray
 class group bnr.
Doc: \var{bnr} being a big
 ray number field as output by \kbd{bnrinit}, and \var{chi} being a row vector
 representing a \idx{character} as expressed on the generators of the ray
 class group, gives the conductor of this character as a modulus.