anchor.diff:        real(rs),intent(in) :: VF_in(:), C_in(:,:,:), rh_in(:)
         real(rs),intent(out) :: Cave(6,6), rhave
         integer :: i,n
  -!      real(rs),allocatable :: VF(:)
         
   !  Get size of arrays and check they're consistent
         n = size(VF_in)
  
positive.code:          write(0,'(a)') 'anisotropy_ajn: CIJ_Reuss_av: C must be nx6x6 array.'
           stop
        endif
        
  !  Allocate space for arrays
  !      allocate(VF(n))
        
  !  Normalise the volume fractions to sum to unity
  !      VF = VF_in / sum(VF_in)
        
  !  Construct Reuss average
        Cave = 0.  ;  S = 0.;  rhave = 0.
  
negative.code:       real(rs),intent(in) :: VF_in(:), C_in(:,:,:), rh_in(:)
        real(rs),intent(out) :: Cave(6,6), rhave
        integer :: i,n
        real(rs) :: S(6,6), S_in(6,6), C_temp(6,6)
        
  !  Get size of arrays and check they're consistent
  