anchor.diff:  
      USE FAST_Solver
      USE FAST_Linear
  -   
  +
      IMPLICIT NONE
   
   CONTAINS
  
positive.code:    !.................................................................
     ! write the data that potentially changes each time step:
     !.................................................................
        
     ! PolyData (.vtp) - Serial vtkPolyData (unstructured) file
     FileName = TRIM(p_FAST%OutFileRoot)//'.WaveSurface.t'//TRIM(Num2LStr(y_FAST%VTK_count))//'.vtp'
        
     call WrVTK_header( FileName, NumberOfPoints, NumberOfLines, NumberOfPolys, Un, ErrStat2, ErrMsg2 )    
        if (ErrStat2 >= AbortErrLev) return
  
negative.code:    ELSE if (allocated(ED%Input) .and. allocated(ED%Output)) then
        ! ElastoDyn
        DO K=1,NumBl        
           call MeshWrVTK(p_FAST%TurbinePos, ED%Output(1)%BladeLn2Mesh(K), trim(VTK_path)//'.ED_BladeLn2Mesh_motion'//trim(num2lstr(k)), y_FAST%VTK_count, p_FAST%VTK_fields, ErrStat2, ErrMsg2, Twidth )
           call MeshWrVTK(p_FAST%TurbinePos, ED%Input(1)%BladePtLoads(K), trim(VTK_path)//'.ED_BladePtLoads'//trim(num2lstr(k)), y_FAST%VTK_count, p_FAST%VTK_fields, ErrStat2, ErrMsg2, Twidth, ED%Output(1)%BladeLn2Mesh(K) )
        END DO      
     END IF
              
  