PetscOptionsGetScalar

Gets the scalar value for a particular option in the database.

Synopsis

#include "petscsys.h"   
PetscErrorCode PetscOptionsGetScalar(PetscOptions options, const char pre[], const char name[], PetscScalar *dvalue, PetscBool *set)

Not Collective

Input Parameters

• options - options database, use NULL for default global database

• pre - string to prepend to each name or NULL

• name - the option one is seeking

Output Parameters

• dvalue - the scalar value to return

• set - PETSC_TRUE if found, else PETSC_FALSE

Example Usage

A complex number 2+3i must be specified with NO spaces

Note

If the user does not supply the option dvalue is NOT changed. Thus you should ALWAYS initialize dvalue if you access it without first checking if the set flag is true.

See Also

PetscOptionsGetInt(), PetscOptionsHasName(), PetscOptionsGetString(), PetscOptionsGetIntArray(), PetscOptionsGetRealArray(), PetscOptionsBool(), PetscOptionsName(), PetscOptionsBegin(), PetscOptionsEnd(), PetscOptionsHeadBegin(), PetscOptionsStringArray(), PetscOptionsRealArray(), PetscOptionsScalar(), PetscOptionsBoolGroupBegin(), PetscOptionsBoolGroup(), PetscOptionsBoolGroupEnd(), PetscOptionsFList(), PetscOptionsEList()

Level

beginner

Location

src/sys/objects/options.c

Examples

src/ksp/ksp/tutorials/ex25.c
src/dm/impls/stag/tutorials/ex1.c
src/dm/impls/stag/tutorials/ex4.c
src/ksp/ksp/tutorials/ex49.c
src/ts/tutorials/ex21.c
src/ts/tutorials/ex45.c
src/snes/tutorials/ex58.c

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