anchor.diff:              v_perturbation=0
           endif
           
  -        print*, maxval(u_perturbation), maxval(v_perturbation)
  +        write(*,*) "Max U perturb:",maxval(u_perturbation), "Max V perturb:",maxval(v_perturbation)
           if (use_spatial_linear_fields) then
               if ((.not.allocated(hi_u_LUT) .and. (.not.reverse)) .or. ((.not.allocated(rev_u_LUT)) .and. reverse)) then
                   
  
positive.code:             ! Compute 2D k and l wavenumber fields (could be stored in options or domain or something)
              offset=pi/domain%dx
              gain=2*offset/(nx-1)
              k(:,1) = (/((i*gain-offset),i=0,nx-1)/)
              do i=2,ny
                  k(:,i)=k(:,1)
              enddo
              
              gain=2*offset/(ny-1)
              l(1,:) = (/((i*gain-offset),i=0,ny-1)/)
              do i=2,nx
                  l(i,:)=l(1,:)
              enddo
  
negative.code:             nsq_calibration=1
      
              if (use_nsq_calibration) then
                  write(*,*) "Reading Linear Mask"
                  write(*,*) "  from file: "//trim(options%nsq_calibration_file)
                  write(*,*) "  varname: "//trim(options%nsq_calibration_var)
                  call io_read2d(options%nsq_calibration_file,options%nsq_calibration_var,domain%nsq_calibration)
                  nsq_calibration=domain%nsq_calibration
                  
  