# How to know vertex points of a segmented model(stl)?

**URL:** <https://discourse.slicer.org/t/how-to-know-vertex-points-of-a-segmented-model-stl/40589>\
**Category:** Support\
**Created:** [December 9, 2024, 6:50pm UTC](https://discourse.slicer.org/t/how-to-know-vertex-points-of-a-segmented-model-stl/40589 "2024-12-09T18:50:01Z")\
**Posts on this page:** 3\
**Page:** 1

<div class="post-metadata">

**Author:** ![Puja\_Ghosh](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/puja_ghosh/32/77922_2.png) [@Puja\_Ghosh](https://discourse.slicer.org/u/Puja_Ghosh)\
**Post date:** [December 9, 2024, 6:50pm UTC](https://discourse.slicer.org/t/how-to-know-vertex-points-of-a-segmented-model-stl/40589/1 "2024-12-09T18:50:01Z")

</div>

I have done segmentation of a model in stl file. But I want to know how many vertices points do the stl model have on it? How can I know about the vertices points?

---

<div class="post-metadata">

**Author:** ![mau\_igna\_06](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/mau_igna_06/32/9056_2.png) [@mau\_igna\_06](https://discourse.slicer.org/u/mau_igna_06)\
**Post date:** [December 9, 2024, 8:34pm UTC](https://discourse.slicer.org/t/how-to-know-vertex-points-of-a-segmented-model-stl/40589/2 "2024-12-09T20:34:49Z")

</div>

In python:  
`nOfPoints = getNode('myModel').GetMesh().GetNumberOfPoints()`

For the number of vertices, I guess you mean, points from the border edges of an open mesh, then you can use [this filter](https://vtk.org/doc/nightly/html/classvtkFeatureEdges.html) with only the option BoundaryEdgesOn

HIH

---

<div class="post-metadata">

**Author:** ![Puja\_Ghosh](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/puja_ghosh/32/77922_2.png) [@Puja\_Ghosh](https://discourse.slicer.org/u/Puja_Ghosh)\
**Post date:** [December 9, 2024, 8:42pm UTC](https://discourse.slicer.org/t/how-to-know-vertex-points-of-a-segmented-model-stl/40589/3 "2024-12-09T20:42:05Z")

</div>

Thank you so much for the information.  
I wanted to know if there is any built in feature or function in 3D Slicer for this? I know, in 3D Slicer, it allows to do targeted value meshing ( through surface toolbox). But I want to know vertex points before any targeted meshing (just after doing segmentation)? And is the filter (that you mentioned) applicable in 3D slicer directly?