anchor.diff:      type(operat), intent(out) :: this
       complex(wp), intent(in) :: val(:)
       integer, intent(in) :: col(:),ptr(:)
  -    integer :: i
  +    ! integer :: i
       if (size(val)==0) then
         call operat_init(this,1,1)
         this%m = 1
  
positive.code:     ! Sparse density matrix from pure state
      complex(wp), intent(in) :: psi(:)
      type(operat), intent(out) :: rho
      type(operat) :: a,b
      rho = ket_to_operat(psi)*bra_to_operat(conjg(psi))
    end subroutine
  
  
negative.code:     complex(KIND=wp) , dimension(:), intent(in) :: x
      complex(KIND=wp) , dimension(:), intent(out) :: y
      integer, intent(out) :: ierr
      integer :: m,n,ofs,i,pntr
      ! integer :: base
      ! character :: diag,type,part
      ierr = -1
      m = size(y)
      n = size(x)
  