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 databasepre - 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, elsePETSC_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#
Examples#
src/ksp/ksp/tutorials/ex49.c
src/ts/tutorials/ex21.c
src/dm/impls/stag/tutorials/ex4.c
src/snes/tutorials/ex58.c
src/dm/impls/stag/tutorials/ex1.c
src/ksp/ksp/tutorials/ex25.c
src/ts/tutorials/ex45.c
Index of all Sys routines
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Index of all manual pages