C CINVAQ    SOURCE    CHAT      05/01/12    22:02:43     5004           

      SUBROUTINE C_INVARI_Q (SIG,N,Q)
      IMPLICIT INTEGER(I-N)
      integer n
      complex*16 sig(n),q,J2
      call C_Invari_J2(sig,n,J2)
      if (abs(j2).le.0.D0) then 
        q=1.D-17
        return
      endif
      q=sqrt(3.D0*J2)
      return
      end