DMAddBoundary#

Add a boundary condition to a model represented by a DM

Synopsis#

#include "petscdm.h"          
#include "petscdmlabel.h"     
#include "petscds.h"     
PetscErrorCode DMAddBoundary(DM dm, DMBoundaryConditionType type, const char name[], DMLabel label, PetscInt Nv, const PetscInt values[], PetscInt field, PetscInt Nc, const PetscInt comps[], void (*bcFunc)(void), void (*bcFunc_t)(void), void *ctx, PetscInt *bd)

Collective

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

  • label - The label defining constrained points

  • Nv - The number of DMLabel values for constrained points

  • values - An array of values for constrained points

  • field - The field to constrain

  • Nc - 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

  • ctx - An optional user context for bcFunc

Output Parameter#

  • bd - (Optional) Boundary number

Options Database Keys#

  • -bc_ - Overrides the boundary ids

  • -bc__comp - Overrides the boundary components

Notes#

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

 void 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:

  void 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#

DM Basics, DM, DSGetBoundary(), PetscDSAddBoundary()

Level#

intermediate

Location#

src/dm/interface/dm.c

Examples#

src/snes/tutorials/ex20.c
src/tao/tutorials/ex1.c
src/snes/tutorials/ex11.c
src/snes/tutorials/ex17.c
src/snes/tutorials/ex71.c
src/snes/tutorials/ex62.c
src/snes/tutorials/ex23.c
src/snes/tutorials/ex56.c
src/tao/tutorials/ex2.c
src/snes/tutorials/ex63.c


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