petsc-3.14.1 2020-11-03
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DMAddBoundary

Add a boundary condition to the model

Synopsis

#include "petscdm.h"          
#include "petscdmlabel.h"     
#include "petscds.h"     
PetscErrorCode DMAddBoundary(DM dm, DMBoundaryConditionType type, const char name[], const char labelname[], PetscInt field, PetscInt numcomps, const PetscInt *comps, void (*bcFunc)(void), void (*bcFunc_t)(void), PetscInt numids, const PetscInt *ids, void *ctx)
Collective on dm

Input Parameters

dm - The DM, with a PetscDS that matches the problem being constrained
type - The type of condition, e.g. DM_BC_ESSENTIAL_ANALYTIC/DM_BC_ESSENTIAL_FIELD (Dirichlet), or DM_BC_NATURAL (Neumann)
name - The BC name
labelname - The label defining constrained points
field - The field to constrain
numcomps - The number of constrained field components (0 will constrain all fields)
comps - An array of constrained component numbers
bcFunc - A pointwise function giving boundary values
bcFunc_t - A pointwise function giving the time deriative of the boundary values, or NULL
numids - The number of DMLabel ids for constrained points
ids - An array of ids for constrained points
ctx - An optional user context for bcFunc

Options Database Keys

-bc_<boundary name> <num> - Overrides the boundary ids
-bc_<boundary name>_comp <num> - Overrides the boundary components

Note

Both bcFunc abd bcFunc_t will depend on the boundary condition type. If the type if DM_BC_ESSENTIAL, Then the calling sequence is

bcFunc(PetscInt dim, PetscReal time, const PetscReal x[], PetscInt Nc, PetscScalar bcval[])

If the type is DM_BC_ESSENTIAL_FIELD or other _FIELD value, then the calling sequence is

bcFunc(PetscInt dim, PetscInt Nf, PetscInt NfAux,
       const PetscInt uOff[], const PetscInt uOff_x[], const PetscScalar u[], const PetscScalar u_t[], const PetscScalar u_x[],
       const PetscInt aOff[], const PetscInt aOff_x[], const PetscScalar a[], const PetscScalar a_t[], const PetscScalar a_x[],
       PetscReal time, const PetscReal x[], PetscScalar bcval[])

dim - the spatial dimension
Nf - the number of fields
uOff - the offset into u[] and u_t[] for each field
uOff_x - the offset into u_x[] for each field
u - each field evaluated at the current point
u_t - the time derivative of each field evaluated at the current point
u_x - the gradient of each field evaluated at the current point
aOff - the offset into a[] and a_t[] for each auxiliary field
aOff_x - the offset into a_x[] for each auxiliary field
a - each auxiliary field evaluated at the current point
a_t - the time derivative of each auxiliary field evaluated at the current point
a_x - the gradient of auxiliary each field evaluated at the current point
t - current time
x - coordinates of the current point
numConstants - number of constant parameters
constants - constant parameters
bcval - output values at the current point

See Also

DMGetBoundary(), PetscDSAddBoundary()

Level

developer

Location

src/dm/interface/dm.c

Examples

src/dm/impls/plex/tutorials/ex2.c.html
src/snes/tutorials/ex12.c.html
src/snes/tutorials/ex17.c.html
src/snes/tutorials/ex56.c.html
src/snes/tutorials/ex62.c.html
src/snes/tutorials/ex77.c.html
src/ts/tutorials/ex45.c.html
src/ts/tutorials/ex46.c.html
src/ts/tutorials/ex48.c.html
src/tao/tutorials/ex1.c.html
src/tao/tutorials/ex2.c.html

Index of all DM routines
Table of Contents for all manual pages
Index of all manual pages