This code implements the CGS (Conjugate Gradient Squared) method.
Does not require a symmetric matrix. Does not apply transpose of the matrix.
Supports left and right preconditioning, but not symmetric.
Has this weird support for doing the convergence test with the natural norm, I assume this works only with no preconditioning and symmetric positive definite operator.
**** -*** Sonneveld, 1989.
KSP: Linear System Solvers,
Index of all KSP routines
Table of Contents for all manual pages
Index of all manual pages