BIB-VERSION:: CS-TR-v2.0 ID:: STAN//NA-M-89-01 ENTRY:: January 28, 1996 ORGANIZATION:: Stanford University, Department of Computer Science, Numerical Analysis Project TITLE:: Iterative methods for cyclically reduced non-self-adjoint linear systems TYPE:: Manuscript AUTHOR:: Elman, Howard C. AUTHOR:: Golub, Gene H. DATE:: February 1989 PAGES:: 32 ABSTRACT:: We study iterative methods for solving linear systems of the type arising from two-cyclic discretizations of non-self-adjoint two-dimensional elliptic partial differential equations. A prototype is the convection-diffusion equation. The methods consist of applying one step of cyclic reduction, resulting in a "reduced system" of half the order of the original discrete problem, combined with a reordering and a block iterative technique for solving the reduced system. For constant coefficient problems, we present analytic bounds on the spectral radii of the iteration matrices in terms of cell Reynolds numbers that show the methods to be rapidly convergent. In addition, we describe numerical experiments that supplement the analysis and that indicate that the methods compare favorably with methods for solving the "unreduced" system. NOTES:: [Adminitrivia V1/Prg/19960128] END:: STAN//NA-M-89-01