# EPSGetInvariantSubspaceLeft

Gets an orthonormal basis of the computed left invariant subspace (only available in two-sided eigensolvers).

### Synopsis

    #include "slepceps.h"
    PetscErrorCode EPSGetInvariantSubspaceLeft(EPS eps,Vec *v)

Not Collective, but vectors are shared by all processors that share the EPS

### Input Parameter

eps - the eigensolver context

### Output Parameter

v - an array of vectors

### Notes

This function should be called after EPSSolve() has finished.

The user should provide in v an array of nconv vectors, where nconv is the value returned by EPSGetConverged().

The first k vectors returned in v span a left invariant subspace associated with the first k computed eigenvalues (note that this is not true if the k-th eigenvalue is complex and matrix A is real; in this case the first k+1 vectors should be used). A left invariant subspace Y of A satisfies y'A in Y for all y in Y (a similar definition applies for generalized eigenproblems).

### See Also

EPSGetEigenpair(), EPSGetConverged(), EPSSolve(), EPSGetInvariantSubspace

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