# Plot on Intersection Curves yields incorrect line plot

**URL:** https://discourse.paraview.org/t/plot-on-intersection-curves-yields-incorrect-line-plot/8471
**Category:** Development
**Tags:** vtk
**Created:** [November 23, 2021, 10:33pm UTC](https://discourse.paraview.org/t/plot-on-intersection-curves-yields-incorrect-line-plot/8471 "2021-11-23T22:33:10Z")
**Posts on this page:** 2
**Page:** 1

<div class="post-metadata">

### Author: ![gnikit](https://discourse.paraview.org/user_avatar/discourse.paraview.org/gnikit/32/6443_2.png) [@gnikit](https://discourse.paraview.org/u/gnikit)
#### Post date: [November 23, 2021, 10:33pm UTC](https://discourse.paraview.org/t/plot-on-intersection-curves-yields-incorrect-line-plot/8471/1 "2021-11-23T22:33:10Z")

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I am trying to get the line plot of the intersection of spherical shell with a plane along the z-axis using a `PlotOnIntersectionCurves` filter but the resulting line chart is vastly different from when the data are extracted and plotted with some other external tool e.g. Python and matplotlib.

Am I do something wrong/missing something obvious in ParaView?

## Steps to replicate

1. `Filters > Plot on Intersection Curves`
2. Set `Plane Parameters` for intersection curve to:  
Origin: 0, 0, 0.5  
Normal: 0, 0, 1

## Paraview output

 ![image](https://discourse.paraview.org/uploads/default/original/2X/a/ab23f046b13dfb1b215cbfbe6fedbab83589d994.png)

## Actual result

 ![image](https://discourse.paraview.org/uploads/default/original/2X/b/bf932715e281a1ed5e853c936a75e38186e2c73e.png)

The result albeit oscillatory agrees with the “true” solution for our problem

 ![image](https://discourse.paraview.org/uploads/default/original/2X/9/9934c0811454533c1122bb96f564ce44e1b9731b.png)

## Files

[rad\_adams\_pincell.detector.Group1.Neutron.1.vtu](https://discourse.paraview.org/uploads/short-url/ajEkaT3ha35AlHiYvKI92vsg4w4.vtu) (49.5 KB)

## Additional info

Paraview 5.10.0-RC1

---

<div class="post-metadata">

### 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: [November 24, 2021, 12:55am UTC](https://discourse.paraview.org/t/plot-on-intersection-curves-yields-incorrect-line-plot/8471/2 "2021-11-24T00:55:37Z")

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Since your data contains a lot of duplicate points, you need to remove them first. Therefore, before applying the **Plot On Intersection Curves** filter, use the **Extract Surface** filter to convert it to vtkPolyData, and then run the **Clean filter** with the following options:

- **Tolerance Is Absolute** : On
- **Absolute Tolerance** : 0.001

The result will look something like this.

 ![angular_flux](https://discourse.paraview.org/uploads/default/original/2X/2/2b950cc597484d7901af968bdc3ef6cc9248980a.png)