# Regional attributes
**URL:** https://community.freefem.org/t/regional-attributes/3338
**Category:** General Discussion
**Created:** [June 23, 2024, 3:31am UTC](https://community.freefem.org/t/regional-attributes/3338 "2024-06-23T03:31:11Z")
**Posts on this page:** 10
**Page:** 1
### Author:  [@qingYang](https://community.freefem.org/u/qingYang)
#### Post date: [June 23, 2024, 3:31am UTC](https://community.freefem.org/t/regional-attributes/3338/1 "2024-06-23T03:31:11Z")
Hello everyone, may I ask how the Regional attributes in the regionlist are generated when using Tetgen to generate mesh? how to get “145” as follow?
real[int] domain =[1.5,pi,0.75,145,0.0025];
mesh3 Thfinal = tetg(Th33,switch=“paAAQY”,regionlist=domain);
---
### Author:  [@frederichecht](https://community.freefem.org/u/frederichecht)
#### Post date: [June 24, 2024, 10:34am UTC](https://community.freefem.org/t/regional-attributes/3338/2 "2024-06-24T10:34:07Z")
I think you get a region number = 145 if the point [1.5,pi,0.75] is in the discrete domain , Pay attention to curved domain.
---
### Author:  [@qingYang](https://community.freefem.org/u/qingYang)
#### Post date: [June 24, 2024, 1:02pm UTC](https://community.freefem.org/t/regional-attributes/3338/3 "2024-06-24T13:02:55Z")
> [@qingYang](#):
>
> attributes
Thank you for your reply, Professor.
I tested using a simple case in the manual, where regional attributes=Th (x, y, z). region, but the results did not match the region list. I hope to receive your further explanation.
[tet.edp](https://community.freefem.org/uploads/short-url/6iFcLysTIk1V1JRlU2ramYiKL0e.edp) (9.8 KB)
---
### Author:  [@frederichecht](https://community.freefem.org/u/frederichecht)
#### Post date: [June 24, 2024, 1:30pm UTC](https://community.freefem.org/t/regional-attributes/3338/4 "2024-06-24T13:30:02Z")
Some correction, remark the region number od meshS is the surface number non a volume number.
```auto
load "tetgen"
{
real hs = 0.1; // mesh size on sphere
int[int] N=[20,20,20];
real [int,int] B=[[-1,1],[-1,1],[-1,1]];
int [int,int] L=[[1,2],[3,4],[5,6]];
////////////////////////////////
meshS ThH = SurfaceHex(N,B,L,1);
meshS ThS =Sphere(0.5,hs,7,1); // "gluing" surface meshs to tolat boundary meshes
cout << " xxxx" << ThH.nv << " " << ThS.nv << endl;
meshS ThHS=ThH+ThS;
plot(ThHS);
// soory MeshS no mesh3 wrong ..
real voltet=(hs^3)/6.;
cout << " voltet = " << voltet << endl;
real[int] domaine = [0,0,0,1,voltet,0,0,0.7,2,voltet];
mesh3 Th = tetg(ThHS,switch="pqaAAYYQ",nbofregions=2,regionlist=domaine);
cout << "3d regions " << regions(Th) << endl;
cout << " Th 3d = (0,0,0) " << Th(0,0,0).region<< endl;
cout << " Th 3d = (0,0,0.7)" << Th(0,0,0.7).region<< endl;
plot(Th,wait=1);
}
```
---
### Author:  [@qingYang](https://community.freefem.org/u/qingYang)
#### Post date: [June 24, 2024, 2:59pm UTC](https://community.freefem.org/t/regional-attributes/3338/5 "2024-06-24T14:59:51Z")
Thank you for your reply, Professor. If this number comes from a 3D mesh, but the 3D mesh requires this number to be generated, is this contradictory? For example, in the following case, how to determine this number in “int [int] domain”?
[test.edp](https://community.freefem.org/uploads/short-url/2XlOKeWOS8ehOKBtI3CXwphiQyT.edp) (2.1 KB)
---
### Author:  [@fb77](https://community.freefem.org/u/fb77)
#### Post date: [June 24, 2024, 3:31pm UTC](https://community.freefem.org/t/regional-attributes/3338/6 "2024-06-24T15:31:42Z")
The 4th argument (out of 5) of each region description in “regionlist” sets the label. You can choose it as you like!
If you define as in your file
`real[int] domaine = [0.2,0.2,1,0,voltet];`
then the label of the region will be 0.
If you set
`real[int] domaine = [0,0,0,1,voltet,0,0,0.7,2,voltet];`
then you will have two regions, the first with region label 1, and the second with region label 2.
---
### Author:  [@qingYang](https://community.freefem.org/u/qingYang)
#### Post date: [June 25, 2024, 12:57am UTC](https://community.freefem.org/t/regional-attributes/3338/8 "2024-06-25T00:57:58Z")
Thank you for your help, Professor. In the following case, I did this, but the program process was killed without any errors，can you help me? please
[test.edp](https://community.freefem.org/uploads/short-url/rx8UtKiQ2h0YYaZOsmVdoVIA9yX.edp) (2.2 KB)
---
### Author:  [@fb77](https://community.freefem.org/u/fb77)
#### Post date: [June 25, 2024, 7:34am UTC](https://community.freefem.org/t/regional-attributes/3338/9 "2024-06-25T07:34:21Z")
I don’t see any problem in your code, it terminates normally after doing what it is asked to do!
---
### Author:  [@qingYang](https://community.freefem.org/u/qingYang)
#### Post date: [June 25, 2024, 7:57am UTC](https://community.freefem.org/t/regional-attributes/3338/10 "2024-06-25T07:57:12Z")
Thank you, professor. I am looking for the reason for its abnormal termination. Have a good day
---
### Author:  [@qingYang](https://community.freefem.org/u/qingYang)
#### Post date: [June 25, 2024, 11:53am UTC](https://community.freefem.org/t/regional-attributes/3338/11 "2024-06-25T11:53:07Z")
Make a brief mark here so that friends who have the same questions as me can refer to it. Thank you again to the two professors.
Solution: 1. The number in the region list {4th} can be given freely by oneself; 2. If the program terminates inexplicably, check if (x, y, z) in the regionlist exceeds the limit