# Q-criteria colored by velocity magnitude

**URL:** https://discourse.paraview.org/t/q-criteria-colored-by-velocity-magnitude/14643
**Category:** ParaView Support
**Created:** [May 16, 2024, 3:00pm UTC](https://discourse.paraview.org/t/q-criteria-colored-by-velocity-magnitude/14643 "2024-05-16T15:00:07Z")
**Posts on this page:** 3
**Page:** 1

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### Author: ![xq520](https://discourse.paraview.org/letter_avatar_proxy/v4/letter/x/43a26b/32.png) [@xq520](https://discourse.paraview.org/u/xq520)
#### Post date: [May 16, 2024, 3:00pm UTC](https://discourse.paraview.org/t/q-criteria-colored-by-velocity-magnitude/14643/1 "2024-05-16T15:00:07Z")

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Hello everyone, I want to get the Isosurfaces of Q-criteria colored by velocity magnitude. And I used the Gradient filiter, but there is no option Q-criteria. Could someone give me some advice? The file is attached.

> **[5.vtu](https://drive.google.com/file/d/1Pg3w_qxjD3NTnuE82Bmmoq_e2tNUN7CW/view?usp=drive_link)**
>
> Google Drive file.

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### Author: ![woodscn](https://discourse.paraview.org/user_avatar/discourse.paraview.org/woodscn/32/3226_2.png) [@woodscn](https://discourse.paraview.org/u/woodscn)
#### Post date: [May 16, 2024, 5:57pm UTC](https://discourse.paraview.org/t/q-criteria-colored-by-velocity-magnitude/14643/2 "2024-05-16T17:57:07Z")

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To compute Q-criterion (and Vorticity and Divergence) you have to enable the advanced filter properties. It’s a little gear icon right by the Delete and help (?) buttons in the Properties window.

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### Author: ![xq520](https://discourse.paraview.org/letter_avatar_proxy/v4/letter/x/43a26b/32.png) [@xq520](https://discourse.paraview.org/u/xq520)
#### Post date: [May 20, 2024, 8:27am UTC](https://discourse.paraview.org/t/q-criteria-colored-by-velocity-magnitude/14643/4 "2024-05-20T08:27:02Z")

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Thanks a lot. I want to get span-average data across the z direction. Could you give me some advice?