# How to extract boundary data

**URL:** https://community.freefem.org/t/how-to-extract-boundary-data/2612
**Category:** General Discussion
**Created:** [July 18, 2023, 4:38am UTC](https://community.freefem.org/t/how-to-extract-boundary-data/2612 "2023-07-18T04:38:08Z")
**Posts on this page:** 1
**Page:** 1

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### Author: ![jawahar264](https://yyz2.discourse-cdn.com/flex030/user_avatar/community.freefem.org/jawahar264/32/1783_2.png) [@jawahar264](https://community.freefem.org/u/jawahar264)
#### Post date: [July 18, 2023, 4:38am UTC](https://community.freefem.org/t/how-to-extract-boundary-data/2612/1 "2023-07-18T04:38:08Z")

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i want to plot the lift on asymmetric airfoil. i solved the problem but no idea how to extract the data on airfoil and plot it in paraview