Abstract

Multigraph 2.1 is an algebraic multilevel solver for large sparse systems of linear equations. The package takes as input just the system matrix in a sparse matrix format and constructs a hierarchy of coarse matrices based on the sparse matrix graph. The multigraph solver is written in Fortran90 and is based on the Fortran77 solver included in the PLTMG 9.0 package. The Multigraph 2.1 distribution contains the basic solver routines that can be incorporated into user applications, and a driver program with a web browser interface (WEBGUI 1.0) and graphics package that can be used independently to demonstrate and test the solver.