# Proyection from a mesh to another

**URL:** https://community.freefem.org/t/proyection-from-a-mesh-to-another/1970
**Category:** General Discussion
**Created:** [August 29, 2022, 8:23am UTC](https://community.freefem.org/t/proyection-from-a-mesh-to-another/1970 "2022-08-29T08:23:54Z")
**Posts on this page:** 1
**Page:** 1

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### Author: ![miguelpicos](https://avatars.discourse-cdn.com/v4/letter/m/8797f3/32.png) [@miguelpicos](https://community.freefem.org/u/miguelpicos)
#### Post date: [August 29, 2022, 8:23am UTC](https://community.freefem.org/t/proyection-from-a-mesh-to-another/1970/1 "2022-08-29T08:23:54Z")

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Hi everyone,

I would like to know if FreeFEM has some proyection routine between two meshes. The named “A Fast Finite Element Interpolator” computes a interpolation of the meshes but that does not satisfy properties as:  
 \int\_{\Omega} u\_{H} = \int\_{\Omega} u\_{h}   
where u\_{H} is the solution over a mesh of \Omega and u\_{h} is his interpolation/proyection over a different mesh of the same domain.

Is there some function that i could use to implement this kind of thing or do i have to code myself this functions?

Thanks