Modified Incomplete Cholesky Preconditioners for 2D Resistivity Modeling

P336 Modified Incomplete Cholesky preconditioners for 2D resistivity modeling Summary 1 We present two modified Incomplete Cholesky factorization preconditioners for symmetric banded linear systems. The first approach normalizes the matrix with respect to its diagonal before the incomplete factorization removing the operation of division from the inner loop. An additional transformation is employed in the second preconditioner to remove the first codiagonals of the matrix. In both cases we take into account the remainder of the factorization by performing an additional iteration within the preconditioned conjugate gradient method. Numerical experiments are performed in a finite-difference approximation of the electric potential