PetscOptionsReal#
Gets a PetscReal value for a particular option in the database.
Synopsis#
#include <petscoptions.h>
PetscErrorCode PetscOptionsReal(const char opt[], const char text[], const char man[], PetscReal currentvalue, PetscReal *value, PetscBool *set)
Logically Collective on the communicator passed in PetscOptionsBegin()
Input Parameters#
opt - option name
text - short string that describes the option
man - manual page with additional information on option
currentvalue - the current value; caller is responsible for setting this value correctly. Normally this is done with either
PetscOptionsReal(..., obj->value,&obj->value,...) or
value = defaultvalue
PetscOptionsReal(..., value,&value,&set);
if (set) {
Output Parameters#
value - the value to return
set -
PETSC_TRUEif found, elsePETSC_FALSE
Notes#
If the user does not supply the option at all value is NOT changed. Thus
you should ALWAYS initialize value if you access it without first checking that set is PETSC_TRUE.
The currentvalue passed into this routine does not get transferred to the output value variable automatically.
Must be used between a PetscOptionsBegin() and a PetscOptionsEnd()
See Also#
PetscOptionsGetReal(), PetscOptionsHasName(), PetscOptionsGetString(), PetscOptionsGetInt(),
PetscOptionsGetIntArray(), PetscOptionsGetRealArray(), PetscOptionsGetBool(),
PetscOptionsInt(), PetscOptionsString(), PetscOptionsReal(), PetscOptionsBool(),
PetscOptionsName(), PetscOptionsBegin(), PetscOptionsEnd(), PetscOptionsHeadBegin(),
PetscOptionsStringArray(), PetscOptionsRealArray(), PetscOptionsScalar(),
PetscOptionsBoolGroupBegin(), PetscOptionsBoolGroup(), PetscOptionsBoolGroupEnd(),
PetscOptionsFList(), PetscOptionsEList(), PetscOptionsBoundedReal(), PetscOptionsRangeReal()
Level#
beginner
Location#
Examples#
src/dm/impls/plex/tutorials/ex9.c
src/ksp/ksp/tutorials/ex35.cxx
src/snes/tutorials/ex31.c
src/dm/impls/plex/tutorials/ex13.c
src/snes/tutorials/ex15.c
src/ksp/ksp/tutorials/ex56.c
src/ksp/ksp/tutorials/ex73.c
src/ksp/ksp/tutorials/ex36.cxx
src/ksp/ksp/tutorials/ex29.c
src/ksp/ksp/tutorials/ex74.c
Index of all Sys routines
Table of Contents for all manual pages
Index of all manual pages