anchor.diff:  
       D => hecMAT%D
   
  +    !$OMP PARALLEL PRIVATE(i)
  +    !$OMP DO
       do i= 1, hecMAT%N
         X1= X(3*i-2)
         X2= X(3*i-1)
  
positive.code:     integer(kind=kint) :: I, K, NZ, IXX
      real(kind=kreal)   :: X1, X2, X3
  
      do I=1,N
        W1(I)=0.D0
        W2(I)=0.D0
        W3(I)=0.D0
      enddo
  
      do NZ=1,MJAD
        do K=IAJAD(NZ),IAJAD(NZ+1)-1
          X1=X(JAJAD(K)*3-2)
          X2=X(JAJAD(K)*3-1)
  
negative.code:       Y(3*i -1)= D(9*i-5)*X1 + D(9*i-4)*X2 + D(9*i-3)*X3
        Y(3*i   )= D(9*i-2)*X1 + D(9*i-1)*X2 + D(9*i  )*X3
      enddo
      !$OMP END DO
      !$OMP END PARALLEL
  
      call MATJAD(hecMAT%N, MJAD, IAJAD, JAJAD, AJAD, JADORD, X, Y, WP1, WP2, WP3)
    end subroutine hecmw_JAD_MATVEC_33
  
  