# Change the label of a region / some elements

**URL:** https://community.freefem.org/t/change-the-label-of-a-region-some-elements/1171
**Category:** General Discussion
**Created:** [August 24, 2021, 2:28pm UTC](https://community.freefem.org/t/change-the-label-of-a-region-some-elements/1171 "2021-08-24T14:28:21Z")
**Posts on this page:** 1
**Page:** 1

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### Author: ![yongxing](https://yyz2.discourse-cdn.com/flex030/user_avatar/community.freefem.org/yongxing/32/3632_2.png) [@yongxing](https://community.freefem.org/u/yongxing)
#### Post date: [August 24, 2021, 2:28pm UTC](https://community.freefem.org/t/change-the-label-of-a-region-some-elements/1171/1 "2021-08-24T14:28:21Z")

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Dear all,

If we have a large mesh **Th** and a small mesh **Ths** on top of it, we know **interpolate()** or  
**transferMat()** can provide the interpolation matrix between these two meshes. My questions are:

1. can we print the elements’ label of **Th** that are covered by **Ths** (in order to compute the interpolation matrix, I believe we already have these information)?
2. can we easily change these elements’ label?

Thank you very much in advance!

Best,  
Yongxing.