Function: znchartokronecker
Section: number_theoretical
C-Name: znchartokronecker
Prototype: GGD0,L,
Help: znchartokronecker(G,chi,{flag=0}): let G be znstar(N,1), let chi
 be a Dirichlet character mod N, return the discriminant D if chi is
 real equal to the Kronecker symbol (D/.) and 0 otherwise. If flag
 is set, return the fundamental discriminant attached to the corresponding
 primitive character.
Doc: Let $G$ be attached to $(\Z/N\Z)^{*}$ (as per \kbd{G = znstar(N,1)})
 and let \kbd{chi} be a Dirichlet character on $(\Z/N\Z)^{*}$, given by

 \item a \typ{VEC}: a standard character on \kbd{bid.gen},

 \item a \typ{INT} or a \typ{COL}: a Conrey index in $(\Z/q\Z)^{*}$ or its
 Conrey logarithm;
 see \secref{se:dirichletchar} or \kbd{??character}.

 If $\fl = 0$, return the discriminant $D$ if \kbd{chi} is real equal to the
 Kronecker symbol $(D/.)$ and $0$ otherwise. The discriminant $D$ is
 fundamental if and only if \kbd{chi} is primitive.

 If $\fl = 1$, return the fundamental discriminant attached to the
 corresponding primitive character.

 \bprog
 ? G = znstar(8,1); CHARS = [1,3,5,7]; \\ Conrey labels
 ? apply(t->znchartokronecker(G,t), CHARS)
 %2 = [4, -8, 8, -4]
 ? apply(t->znchartokronecker(G,t,1), CHARS)
 %3 = [1, -8, 8, -4]
 @eprog
