# Streamtracer from Point Data

**URL:** https://discourse.paraview.org/t/streamtracer-from-point-data/4788
**Category:** ParaView Support
**Tags:** vtk
**Created:** [July 8, 2020, 9:18pm UTC](https://discourse.paraview.org/t/streamtracer-from-point-data/4788 "2020-07-08T21:18:53Z")
**Posts on this page:** 3
**Page:** 1

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### Author: ![David\_Cortes](https://discourse.paraview.org/user_avatar/discourse.paraview.org/david_cortes/32/4442_2.png) [@David\_Cortes](https://discourse.paraview.org/u/David_Cortes)
#### Post date: [July 8, 2020, 9:18pm UTC](https://discourse.paraview.org/t/streamtracer-from-point-data/4788/1 "2020-07-08T21:18:53Z")

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Hi, I have a VTK with only Point Data and Vector data and I would like to generate StreamLines following the Vector Field. I can visualize the vector field using Glyphs but the problem is that Streamtracer doesn’t show anything. The VTK has this format:

```auto
ASCII
DATASET UNSTRUCTURED_GRID
POINTS 132651 double
-100.0 -100.0 -100.0
-100.0 -100.0 -96.0
...
CELLS 0 0

CELL_TYPES 0

POINT_DATA 132651
VECTORS Vectors1 double
1.3865089739273324e-08 6.834997702797794e-08 2.0137151470163464e-08
...

```

Is there anything I’m missing in the VTK file?

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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: [July 8, 2020, 9:31pm UTC](https://discourse.paraview.org/t/streamtracer-from-point-data/4788/2 "2020-07-08T21:31:18Z")

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Cells. You are missing cells.

If you think about it, streamlines don’t make any sense if you don’t have some region of space (i.e. a volume) that has a stream. You don’t have that. You just have some sparse points that define a vector and empty space in between them.

Cells are what define how these sparse points you have are supposed to define what the flow looks like between the points.

For a variety of reasons, the tools for going from just points to a connected region of cells are not great. The most common solution is to use the `Delaunay 3D` filter. It looks like that should work for you.

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<div class="post-metadata">

### Author: ![David\_Cortes](https://discourse.paraview.org/user_avatar/discourse.paraview.org/david_cortes/32/4442_2.png) [@David\_Cortes](https://discourse.paraview.org/u/David_Cortes)
#### Post date: [July 8, 2020, 9:45pm UTC](https://discourse.paraview.org/t/streamtracer-from-point-data/4788/3 "2020-07-08T21:45:17Z")

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Hi, thanks for the tip. I see, I’ll try to generate cell data then.  
I tried the `Delaunay 3D` and it allowed me to generate a stream with `StreamTracer`, thanks so much!