@Arthas007, you can convert a Laplacian PDE into a linear system, as shown on slide 35: http://15462.courses.cs.cmu.edu/fall2020/lecture/pdes/slide_035, and then this is equivalent to a system where Ax=b (depending on the type of system, b might be zero or non-zero), and you would use the linear solver, solve it, and check whether the solution is actually valid for the original system or not
how does b-Ax associate with delta phi = 0?
@Arthas007, you can convert a Laplacian PDE into a linear system, as shown on slide 35: http://15462.courses.cs.cmu.edu/fall2020/lecture/pdes/slide_035, and then this is equivalent to a system where Ax=b (depending on the type of system, b might be zero or non-zero), and you would use the linear solver, solve it, and check whether the solution is actually valid for the original system or not
Yep, @rgrao has it exactly right!