Theorem 1.7.6 Let
C be a code over
F_(q). The following hold:
(i) If
M is a monomial matrix with entries only from
{0,-1,1}, then
C is self-dinal if and only if CM is self-dual.
C~=C_(1)
c=c^(2)<=>c_(1)=c_(1)^(-)
(ii) If
q=3 and
C is equivalenti to
C_(1), then
C is self-dual if and only if
C_(1) is self-dual.
(iii) If
q=4 and
C is equivalent to
C_(1) /then
C is Hermitian self-dual if and only if
C_(1) is Hermitian self-dinal.
c=c^(2 1)<=>c_(1)=c^(2 1)
