# The picture is white and has nothing

**URL:** https://community.freefem.org/t/the-picture-is-white-and-has-nothing/1557
**Category:** General Discussion
**Created:** [February 25, 2022, 3:17am UTC](https://community.freefem.org/t/the-picture-is-white-and-has-nothing/1557 "2022-02-25T03:17:02Z")
**Posts on this page:** 1
**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: [February 25, 2022, 3:17am UTC](https://community.freefem.org/t/the-picture-is-white-and-has-nothing/1557/1 "2022-02-25T03:17:02Z")

</div>

Run the following program with the command（C:\Users\weiqi\>FreeFem++ square.edp or C:\Users\weiqi\>FreeFem+±mpi square.edp -wg), but the picture is white and has nothing.

mesh Th=square(20,20);  
plot(Th);

load “metis”  
//load “scotch”  
//load “parmetis”

fespace Ph(Th,P0);  
Ph color;

metisdual(color[],Th,4);  
plot(color);

 ![image](https://canada1.discourse-cdn.com/flex030/uploads/freefem/original/2X/0/0ea6c818ecd17a61845f83cbe94279866f5f9b7f.png)