# Incorrect area result using closed curve markups measurement

**URL:** <https://discourse.slicer.org/t/incorrect-area-result-using-closed-curve-markups-measurement/19114>\
**Category:** Support\
**Tags:** markups\
**Created:** [August 9, 2021, 9:31am UTC](https://discourse.slicer.org/t/incorrect-area-result-using-closed-curve-markups-measurement/19114 "2021-08-09T09:31:00Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![VincentYu](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/vincentyu/32/69793_2.png) [@VincentYu](https://discourse.slicer.org/u/VincentYu)\
**Post date:** [August 9, 2021, 9:31am UTC](https://discourse.slicer.org/t/incorrect-area-result-using-closed-curve-markups-measurement/19114/1 "2021-08-09T09:31:01Z")

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## OS: Windows10 x64 Slicer version: 4.13.0-2021-08-08 Image used: built-in sample data (Chest CT)

[video link](https://drive.google.com/drive/folders/1wt1j-VD2_dDSvTBLEhFp5nt51M_EKrKm?usp=sharing)  
I found the results of measured area using the closed curve markup with linear curve were inconsistent when I toggled the Enable checkbox in Slicer ver4.11.20210226, see the video “4.11.mp4”.  
I tried to reproduce this problem in Slicer 4.13.0-2021-08-08, but I got 0 cm^2 instead, see the video “4.13.0.mp4”.

 ![4.13.0.PNG](https://us1.discourse-cdn.com/flex002/uploads/slicer/original/3X/0/d/0d3859198e1f85b1fbd325a691ea98fd070daeb6.jpeg)

The results looked fine if I chose spline curve instead of linear curve, and I haven’t tried any other curve type yet.

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**Author:** ![lassoan](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/lassoan/32/13_2.png) [@lassoan](https://discourse.slicer.org/u/lassoan)\
**Post date:** [August 9, 2021, 4:32pm UTC](https://discourse.slicer.org/t/incorrect-area-result-using-closed-curve-markups-measurement/19114/2 "2021-08-09T16:32:38Z")

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Thanks for reporting. I’ve submitted an issue to track this problem:

> <https://github.com/Slicer/Slicer/issues/5780>
>
> Markups closed curve area measurement sometimes returns 0.0 as a result because …Delaunay triangulation fails.
> 
> See user reports:
> \- https://discourse.slicer.org/t/incorrect-area-result-using-closed-curve-markups-measurement/19114
> \- https://discourse.slicer.org/t/why-closed-curve-cannot-generate-baffle-model-in-baffle-planner-module/19076
> 
> \## Environment
> \- Slicer version: Slicer-4.13.0-2021-08-02
> \- Operating system: Windows 10 (probably OS independent)

As a quick workaround, you can increase the resolution of the curve by typing this into the Python console (replace `CC` by the actual name of your curve node):

```python
getNode('CC').SetNumberOfPointsPerInterpolatingSegment(30)

```

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**Author:** ![VincentYu](https://sea2.discourse-cdn.com/flex002/user_avatar/discourse.slicer.org/vincentyu/32/69793_2.png) [@VincentYu](https://discourse.slicer.org/u/VincentYu)\
**Post date:** [August 11, 2021, 2:11am UTC](https://discourse.slicer.org/t/incorrect-area-result-using-closed-curve-markups-measurement/19114/3 "2021-08-11T02:11:41Z")

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Thank you for the workaround, Prof Lasso.