# NEPGetEigenpair

Gets the i-th solution of the eigenproblem as computed by NEPSolve(). The solution consists in both the eigenvalue and the eigenvector.

### Synopsis

    #include "slepcnep.h"
    PetscErrorCode NEPGetEigenpair(NEP nep,PetscInt i,PetscScalar *eig,Vec V)

Logically Collective on NEP

### Input Parameters

| nep | - nonlinear eigensolver context
| i | - index of the solution

### Output Parameters

| eig | - eigenvalue
| V | - eigenvector

### Notes

If PETSc is configured with real scalars, then complex eigenpairs cannot be obtained. Users should use a complex-scalar configuration. This behaviour is different to other SLEPc solvers such as EPS.

The index i should be a value between 0 and nconv-1 (see NEPGetConverged()). Eigenpairs are indexed according to the ordering criterion established with NEPSetWhichEigenpairs().

### See Also

NEPSolve(), NEPGetConverged(), NEPSetWhichEigenpairs()

Location: src/nep/interface/nepsolve.c
Index of all NEP routines
Table of Contents for all manual pages
Index of all manual pages

### Examples

src/nep/examples/tutorials/ex20.c.html
src/nep/examples/tutorials/ex21.c.html
src/nep/examples/tutorials/ex22.c.html