University of Jyväskylä, Department of Mathematical Information Technology, P.O. Box 35 (Agora), 40351 Jyväskylä, Finland. Janne.Martikainen@mit.jyu.fi.
A sparse algebraic multigrid method is studied as a cheap and accurate way to compute approximations of Schur complements of matrices arising from the discretization of some symmetric and positive definite partial differential operators. The construction of such a multigrid is discussed and numerical experiments are used to verify the properties of the method.
(Received November 30 2001)
(Revised October 9 2002)
(Online publication March 15 2003)
Mathematics Subject Classification: