# Hello, about high-order interpolation of 1D DG finite element

**URL:** https://community.freefem.org/t/hello-about-high-order-interpolation-of-1d-dg-finite-element/1989
**Category:** General Discussion
**Created:** [September 6, 2022, 2:23am UTC](https://community.freefem.org/t/hello-about-high-order-interpolation-of-1d-dg-finite-element/1989 "2022-09-06T02:23:15Z")
**Posts on this page:** 2
**Page:** 1

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### Author: ![Qianrui](https://avatars.discourse-cdn.com/v4/letter/q/9fc348/32.png) [@Qianrui](https://community.freefem.org/u/Qianrui)
#### Post date: [September 6, 2022, 2:23am UTC](https://community.freefem.org/t/hello-about-high-order-interpolation-of-1d-dg-finite-element/1989/1 "2022-09-06T02:23:15Z")

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Hello, about the 1DDG high-level interpolation command, I am in FreeFem Documentation Release 4.8, did not find, where can I find? Low-order interpolation P1dcl

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### Author: ![frederichecht](https://yyz2.discourse-cdn.com/flex030/user_avatar/community.freefem.org/frederichecht/32/15_2.png) [@frederichecht](https://community.freefem.org/u/frederichecht)
#### Post date: [September 6, 2022, 3:27pm UTC](https://community.freefem.org/t/hello-about-high-order-interpolation-of-1d-dg-finite-element/1989/2 "2022-09-06T15:27:27Z")

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In the source code, sorry or you can do retro enginery  
form the P1dcL to dof are move a little inside the element of 0.001 so the barycentric coordinate are

0.001, 0.999 and 0.999 , 0.001 to see discontinuity.