# Approximate Algorithms for Poisson's Equation (PDE)

Are there some approximate or randomised algorithms to numerically solve Poisson's Equation in Partial Differential Equations.(http://en.wikipedia.org/wiki/Poisson%27s_equation). The best algorithms I know of are Multigrid methods(http://en.wikipedia.org/wiki/Multigrid_methods), but they are deterministic and are O(n). Are there Randomised or approximate algos to solve this problem.

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I think your question should contain more details. For instance, what is $n$ in $O(n)$ ? –  Denis Serre Dec 22 '10 at 13:24