Solve Laplace equation: how to make the recursion stop?

Hello,

I’m implementing relaxation method to solve Laplaca equation. When the result is convergent enough, I want the recurrsion stops. But I used Nestlist, and cannot see how to make it stop by itself. I test the error until the error is smaller than 10^(-5), then stop it. But I want the algorithm do it by itself.
The algorithm is as following:

Have you tried NestWhileList?

I didn’t know that, I’ll try now. Thanks.