C CINVAP    SOURCE    CHAT      05/01/12    22:02:39     5004           

      SUBROUTINE C_INVARI_P (SIG,N,P)
      IMPLICIT INTEGER(I-N)
      integer n
      complex*16 sig(n),p
      p=-(sig(1)+sig(2)+sig(3))/3.D0
      return
      end