PyAMG

PyAMG is a library of **Algebraic Multigrid (AMG)** solvers with a convenient
Python interface.

AMG is a multilevel technique for solving large-scale linear systems with
optimal or near-optimal efficiency.  Unlike geometric multigrid, AMG requires
little or no geometric information about the underlying problem and develops a
sequence of coarser grids directly from the input matrix. This feature is
especially important for problems discretized on unstructured meshes and
irregular grids.