# QEPSetOptionsPrefix

Sets the prefix used for searching for all QEP options in the database.

### Synopsis

    #include "slepcqep.h"
    PetscErrorCode QEPSetOptionsPrefix(QEP qep,const char *prefix)

Logically Collective on QEP

### Input Parameters

| qep | - the quadratic eigensolver context
| prefix | - the prefix string to prepend to all QEP option requests

### Notes

A hyphen (-) must NOT be given at the beginning of the prefix name. The first character of all runtime options is AUTOMATICALLY the hyphen.

For example, to distinguish between the runtime options for two different QEP contexts, one could call

          QEPSetOptionsPrefix(qep1,"qeig1_")
          QEPSetOptionsPrefix(qep2,"qeig2_")

### See Also

QEPAppendOptionsPrefix(), QEPGetOptionsPrefix()

Location: src/qep/interface/qepopts.c
Index of all QEP routines
Table of Contents for all manual pages
Index of all manual pages