# "Change" function gives error on 3D mesh v 4.4

**URL:** <https://community.freefem.org/t/change-function-gives-error-on-3d-mesh-v-4-4/123>\
**Category:** General Discussion\
**Created:** [September 2, 2019, 2:46pm UTC](https://community.freefem.org/t/change-function-gives-error-on-3d-mesh-v-4-4/123 "2019-09-02T14:46:52Z")\
**Posts on this page:** 2\
**Page:** 1

<div class="post-metadata">

**Author:** ![BeniaminBogosel](https://avatars.discourse-cdn.com/v4/letter/b/3ec8ea/32.png) [@BeniaminBogosel](https://community.freefem.org/u/BeniaminBogosel)\
**Post date:** [September 2, 2019, 2:46pm UTC](https://community.freefem.org/t/change-function-gives-error-on-3d-mesh-v-4-4/123/1 "2019-09-02T14:46:52Z")

</div>

Hello,  
I had a code which worked fine under version 4.2 and which gives an assertion fail when trying to apply the “change” function to change the labels on a 3D mesh. Maybe it has something to do with the surface mesh.  
If you want more details I can provide the mesh and the code to reproduce the error.  
Best regards,  
Beniamin

---

<div class="post-metadata">

**Author:** ![AFourmont](https://yyz2.discourse-cdn.com/flex030/user_avatar/community.freefem.org/afourmont/32/56_2.png) [@AFourmont](https://community.freefem.org/u/AFourmont)\
**Post date:** [September 3, 2019, 9:30am UTC](https://community.freefem.org/t/change-function-gives-error-on-3d-mesh-v-4-4/123/2 "2019-09-03T09:30:16Z")

</div>

Dear user,  
You find a bug, it’s correct on the current version of develop branch  
Axel