# PetscOptionsBegin

Begins a set of queries on the options database that are related and should be displayed on the same window of a GUI that allows the user to set the options interactively. Synopsis: PetscErrorCode PetscOptionsBegin(MPI_Comm comm,const char prefix[],const char title[],const char mansec[])

Collective on MPI_Comm

### Input Parameters

| comm | - communicator that shares GUI
| prefix | - options prefix for all options displayed on window
| title | - short descriptive text, for example "Krylov Solver Options"
| mansec | - section of manual pages for options, for example KSP

Notes: Needs to be ended by a call the PetscOptionsEnd()

Can add subheadings with PetscOptionsHead()

### See Also

PetscOptionsGetReal(), PetscOptionsHasName(), PetscOptionsGetString(), PetscOptionsGetInt(),
PetscOptionsGetIntArray(), PetscOptionsGetRealArray(), PetscOptionsTruth() PetscOptionsInt(), PetscOptionsString(), PetscOptionsReal(), PetscOptionsTruth(), PetscOptionsName(), PetscOptionsBegin(), PetscOptionsEnd(), PetscOptionsHead(), PetscOptionsStringArray(),PetscOptionsRealArray(), PetscOptionsScalar(), PetscOptionsTruthGroupBegin(), PetscOptionsTruthGroup(), PetscOptionsTruthGroupEnd(), PetscOptionsList(), PetscOptionsEList()

Level:intermediate
Location:src/sys/src/objects/ams/../../../../../include/petscoptions.h
Index of all Sys routines
Table of Contents for all manual pages
Index of all manual pages

### Examples

src/ksp/examples/tutorials/ex29.c.html