Improvement of Crout version of ILU preconditioning based on compensation of a diagonal entry for fill-in

Abstract

This paper discusses a variant of the Crout version of Incomplete LU (ILUC) decomposition. Performance of the ILUC decomposition has been reported in the field of earth resource engineering and electromagnetic analysis. We embody a particular strategy for stable convergence of ILUC decomposition by means of compensation of a diagonal entry for fill-in. Numerical experiments indicate that the iterative methods with ILUC decomposition based on compensation of a diagonal entry perform well in view of efficiency, safety of convergence and necessary number of fill-ins as compared with the conventional ILUC decomposition.