# Extracting data from the unstructured grid using vtkplane cutter

**URL:** https://discourse.vtk.org/t/extracting-data-from-the-unstructured-grid-using-vtkplane-cutter/2362
**Category:** Support
**Created:** [December 31, 2019, 9:04pm UTC](https://discourse.vtk.org/t/extracting-data-from-the-unstructured-grid-using-vtkplane-cutter/2362 "2019-12-31T21:04:40Z")
**Posts on this page:** 2
**Page:** 1

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### Author: ![venkatesh](https://discourse.vtk.org/letter_avatar_proxy/v4/letter/v/77aa72/32.png) [@venkatesh](https://discourse.vtk.org/u/venkatesh)
#### Post date: [December 31, 2019, 9:04pm UTC](https://discourse.vtk.org/t/extracting-data-from-the-unstructured-grid-using-vtkplane-cutter/2362/1 "2019-12-31T21:04:40Z")

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Hi,

I am trying to using vtkPlane() and vtkCutter in python to read the unstructured data. I have the volume data and wanted to extract data over a plane. So, I pass the plane location and normal to extract the data. The problem is it extracts data fine for few locations. However, for some other locations, it creates spurious data points as attached in the figure. The red dots are required and blue asterisks are for another plane and it has duplicate/spurious as marked.

 ![Inkedspurious_nodes_LI](https://discourse.vtk.org/uploads/default/original/2X/1/1f3682c5f19659d3a79c34cf867b3f32f8d04ea0.jpeg)

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### Author: ![venkatesh](https://discourse.vtk.org/letter_avatar_proxy/v4/letter/v/77aa72/32.png) [@venkatesh](https://discourse.vtk.org/u/venkatesh)
#### Post date: [January 9, 2020, 4:54pm UTC](https://discourse.vtk.org/t/extracting-data-from-the-unstructured-grid-using-vtkplane-cutter/2362/2 "2020-01-09T16:54:04Z")

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I have a volume unstructured grid data stored in .pvtu files. I needed to extract data at several parallel planes. So, I used vtk plane to do that. The problem I am facing is one plane looks fine as red dots. However, when I read another parallel plane, i am getting spurious blue points as encircled. Could you please help me how to filter those ?
