petsc-3.7.1 2016-05-15
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# KSPTCQMR

A variant of QMR (quasi minimal residual) developed by Tony Chan

### Options Database Keys

see KSPSolve() - Many br Many br

Notes: Supports either left or right preconditioning, but not symmetric Many br

The "residual norm" computed in this algorithm is actually just an upper bound on the actual residual norm. Many brThat is for left preconditioning it is a bound on the preconditioned residual and for right preconditioning Many brit is a bound on the true residual. Many br

### References

1. -Tony F. Chan, Lisette de Pillis, and Henk van der Vorst, Transpose free formulations of Lanczos type methods for nonsymmetric linear systems, Many brNumerical Algorithms, Volume 17, 1998. Many br

### See Also

KSPCreate(), KSPSetType(), KSPType (for list of available types), KSP, KSPTFQMR

Level:beginner
Location:src/ksp/ksp/impls/tcqmr/tcqmr.c
Index of all KSP routines
Table of Contents for all manual pages
Index of all manual pages