EPSSetDeflationSpace

Specify a basis of vectors that constitute the deflation space.

Synopsis

#include "slepceps.h" 
PetscErrorCode EPSSetDeflationSpace(EPS eps,PetscInt n,Vec *ds)
Collective on EPS and Vec

Input Parameter

eps - the eigenproblem solver context
n - number of vectors
ds - set of basis vectors of the deflation space

Notes

When a deflation space is given, the eigensolver seeks the eigensolution in the restriction of the problem to the orthogonal complement of this space. This can be used for instance in the case that an invariant subspace is known beforehand (such as the nullspace of the matrix).

Basis vectors set by a previous call to EPSSetDeflationSpace() are replaced.

The vectors do not need to be mutually orthonormal, since they are explicitly orthonormalized internally.

These vectors persist from one EPSSolve() call to the other, use EPSRemoveDeflationSpace() to eliminate them.

See Also

EPSRemoveDeflationSpace()

Location: src/eps/interface/setup.c
Index of all EPS routines
Table of Contents for all manual pages
Index of all manual pages