Solving a complex PDE in 2D numerically

Hi, I have Matlab and in it, using Matlab PDE Toolbox does provide a solution to my PDE.

I have the following PDE:

 u NABLA^2 - I*u + c = 0

where I is the imaginary number, and NABLA² is the Laplacian in 2D.

Is there a tutorial or something similar that shows how to solve this numerically in MATLAB?

Thanks

[Torsten]

NABLA^2 of what ? Domain ? Boundary conditions ?

Best wishes

Torsten.

[Sergio Manzetti]

I missed this answer. It is NABLA of u(x,y), so u should have been written before NABLA. Domain is {x,y}={-inf, +inf}, B.C. u(x,0)=1, u(0,y)=1