# Modifying the vtk files

**URL:** https://discourse.paraview.org/t/modifying-the-vtk-files/13631
**Category:** ParaView Support
**Created:** [January 4, 2024, 9:32am UTC](https://discourse.paraview.org/t/modifying-the-vtk-files/13631 "2024-01-04T09:32:50Z")
**Posts on this page:** 4
**Page:** 1

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### Author: ![KB92](https://discourse.paraview.org/user_avatar/discourse.paraview.org/kb92/32/10407_2.png) [@KB92](https://discourse.paraview.org/u/KB92)
#### Post date: [January 4, 2024, 9:32am UTC](https://discourse.paraview.org/t/modifying-the-vtk-files/13631/1 "2024-01-04T09:32:50Z")

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I have some vtk files with point data and I want to modify data over some points (changing values or may be multiplying by some factor). After modifying I want to save this as a new .vtk again. Is there a way of doing this in python or paraview. The number of points are very large (120k and even more). An example file is here.  
[solution0000000001.vtk](https://discourse.paraview.org/uploads/short-url/dcybtm5EYZmwGWdDsPVHZF1FsTR.vtk) (824.0 KB)

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### Author: ![mwestphal](https://discourse.paraview.org/user_avatar/discourse.paraview.org/mwestphal/32/17_2.png) [@mwestphal](https://discourse.paraview.org/u/mwestphal)
#### Post date: [January 4, 2024, 9:33am UTC](https://discourse.paraview.org/t/modifying-the-vtk-files/13631/2 "2024-01-04T09:33:46Z")

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Hi,

> [@KB92](#):
>
> I want to modify data over some points (changing values or may be multiplying by some factor).

Filters-\>Calculator

> After modifying I want to save this as a new .vtk again.

File → SaveData

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<div class="post-metadata">

### Author: ![KB92](https://discourse.paraview.org/user_avatar/discourse.paraview.org/kb92/32/10407_2.png) [@KB92](https://discourse.paraview.org/u/KB92)
#### Post date: [January 5, 2024, 12:26pm UTC](https://discourse.paraview.org/t/modifying-the-vtk-files/13631/3 "2024-01-05T12:26:01Z")

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Thank you for your reply. How to use the calculator filter to access specific points of an array? Doesn’t it deal with the whole array?  
I attached an example vtk file here.  
[solution0000007600.zip](https://discourse.paraview.org/uploads/short-url/oogtxF1vbhhIuEbNg72Rx958EOg.zip) (896.3 KB)

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<div class="post-metadata">

### Author: ![mwestphal](https://discourse.paraview.org/user_avatar/discourse.paraview.org/mwestphal/32/17_2.png) [@mwestphal](https://discourse.paraview.org/u/mwestphal)
#### Post date: [January 5, 2024, 12:28pm UTC](https://discourse.paraview.org/t/modifying-the-vtk-files/13631/4 "2024-01-05T12:28:34Z")

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> [@KB92](#):
>
> Doesn’t it deal with the whole array?

Yes

> How to use the calculator filter to access specific points of an array?

If you want to do an actual specific computation, then you should use a programmable filter.