# Selected cell moves when I change time step

**URL:** https://discourse.paraview.org/t/selected-cell-moves-when-i-change-time-step/4471
**Category:** ParaView Support
**Created:** [June 2, 2020, 6:42am UTC](https://discourse.paraview.org/t/selected-cell-moves-when-i-change-time-step/4471 "2020-06-02T06:42:51Z")
**Posts on this page:** 4
**Page:** 1

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### Author: ![AManning](https://discourse.paraview.org/user_avatar/discourse.paraview.org/amanning/32/3944_2.png) [@AManning](https://discourse.paraview.org/u/AManning)
#### Post date: [June 2, 2020, 6:42am UTC](https://discourse.paraview.org/t/selected-cell-moves-when-i-change-time-step/4471/1 "2020-06-02T06:42:51Z")

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I have been trying to plot my variables over time. To do this I have selected the cell(s) in question and then click “plot over time”. This seems simple enough.

Unfortunately when looking at a 3D shape of my results and change the time step, the selected cell moves. I am using version 5.8.0. Has anyone else seen this problem before or knows how to fix it?

 ![image](https://discourse.paraview.org/uploads/default/original/2X/2/2fa941ed8fe1307d7b9cab6c5f5e75c6ffa5628c.png)  
 ![image](https://discourse.paraview.org/uploads/default/original/2X/f/fbf3f60bffa5370d49b6600196ae386f2e673854.png)

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### Author: ![Kenneth\_Moreland](https://discourse.paraview.org/user_avatar/discourse.paraview.org/kenneth_moreland/32/15033_2.png) [@Kenneth\_Moreland](https://discourse.paraview.org/u/Kenneth_Moreland)
#### Post date: [June 2, 2020, 4:04pm UTC](https://discourse.paraview.org/t/selected-cell-moves-when-i-change-time-step/4471/2 "2020-06-02T16:04:45Z")

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The answer probably depends on how you selected the cell and the nature of your data. I’m going to assume that you selected the cell by clicking on the `Select Cells On` button ![pqSurfaceSelectionCell](https://discourse.paraview.org/uploads/default/original/2X/3/35dcea4f31989d2eef33017ac659037fc039c342.svg) and clicking on the cell.

Most likely what is happening is the topology of your mesh is changing from one timestep to another. When you do a selection like this, ParaView records the id of the cell you selected (cells are ordered from 0-_N_). If you load a mesh for a new timestep and the mesh for the next timestep has the cells in a different order, then the selection is going to move.

If you want data to be at a consistent location over time, you might try the `Probe` filter instead.

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### Author: ![Gening\_Dong](https://discourse.paraview.org/user_avatar/discourse.paraview.org/gening_dong/32/10295_2.png) [@Gening\_Dong](https://discourse.paraview.org/u/Gening_Dong)
#### Post date: [November 27, 2023, 8:20pm UTC](https://discourse.paraview.org/t/selected-cell-moves-when-i-change-time-step/4471/3 "2023-11-27T20:20:50Z")

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Hi @Kenneth_Moreland

I met the same problem here. My data is 3D so a volumetric mesh but I want to analyze the surface values so I applied `ExtractSurface`. The selected cells on the 3D mesh didn’t change with time steps but the selected cells on the surface did. I tried `Generate Ids` and `Generate Global Ids` but neither works. Perhaps is the `ExtractSurface` filter change the cell order for every time step? Is there a way to avoid this? Thanks in advance!

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### Author: ![Kenneth\_Moreland](https://discourse.paraview.org/user_avatar/discourse.paraview.org/kenneth_moreland/32/15033_2.png) [@Kenneth\_Moreland](https://discourse.paraview.org/u/Kenneth_Moreland)
#### Post date: [December 5, 2023, 4:02pm UTC](https://discourse.paraview.org/t/selected-cell-moves-when-i-change-time-step/4471/4 "2023-12-05T16:02:24Z")

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@Gening_Dong It could depend on your data. Can you share some of it?