Function: zncharisodd
Section: number_theoretical
C-Name: zncharisodd
Prototype: lGG
Help: zncharisodd(G, chi): let G be znstar(N,1), let chi
be a Dirichlet character mod N, return 1 if and only if chi(-1) = -1
and 0 otherwise.
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{G.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}.
Return $1$ if and only if \kbd{chi}$(-1) = -1$ and $0$ otherwise.
\bprog
? G = znstar(8, 1);
? zncharisodd(G, 1) \\ trivial character
%2 = 0
? zncharisodd(G, 3)
%3 = 1
? chareval(G, 3, -1)
%4 = 1/2
@eprog