# beginner in paraview (problem with variable)

**URL:** https://discourse.paraview.org/t/beginner-in-paraview-problem-with-variable/3229
**Category:** ParaView Support
**Created:** [December 24, 2019, 9:41am UTC](https://discourse.paraview.org/t/beginner-in-paraview-problem-with-variable/3229 "2019-12-24T09:41:50Z")
**Posts on this page:** 2
**Page:** 1

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### Author: ![sobdn21](https://discourse.paraview.org/letter_avatar_proxy/v4/letter/s/45deac/32.png) [@sobdn21](https://discourse.paraview.org/u/sobdn21)
#### Post date: [December 24, 2019, 9:41am UTC](https://discourse.paraview.org/t/beginner-in-paraview-problem-with-variable/3229/1 "2019-12-24T09:41:51Z")

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Hello !  
I’m a beginner in paraview and I have a problem. I created a .stl file on the website tinkercad. I wanted to use paraview to visualize stream flows but when I open my file I don’t have any variable, I only have “the object”. How can I add variables to my file (3 are required to use the stream tracer) ?

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### Author: ![Kenichiro-Yoshimi](https://discourse.paraview.org/letter_avatar_proxy/v4/letter/k/ecc23a/32.png) [@Kenichiro-Yoshimi](https://discourse.paraview.org/u/Kenichiro-Yoshimi)
#### Post date: [December 27, 2019, 2:26am UTC](https://discourse.paraview.org/t/beginner-in-paraview-problem-with-variable/3229/2 "2019-12-27T02:26:08Z")

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STL file cannot store simulation data, it only stores a triangle mesh surface. At first, you need to convert your geometry and simulation data to another format available in ParaView such as \*.vtu, etc.