PETSc version 3.15.5
DMComputeL2GradientDiff
This function computes the L_2 difference between the gradient of a function u and an FEM interpolant solution grad u_h. 
Synopsis
#include "petscdm.h"          
#include "petscdmlabel.h"     
#include "petscds.h"     
PetscErrorCode DMComputeL2GradientDiff(DM dm, PetscReal time, PetscErrorCode (**funcs)(PetscInt, PetscReal, const PetscReal [], const PetscReal[], PetscInt, PetscScalar *, void *), void **ctxs, Vec X, const PetscReal n[], PetscReal *diff)
Collective on dm
Input Parameters
|  | dm | - The DM
, time  - The time | 
|  | funcs | - The gradient functions to evaluate for each field component | 
|  | ctxs | - Optional array of contexts to pass to each function, or NULL. | 
|  | X | - The coefficient vector u_h, a global vector | 
|  | n | - The vector to project along | 
Output Parameter
|  | diff | - The diff ||(grad u - grad u_h) . n||_2 | 
See Also
 DMProjectFunction(), DMComputeL2Diff()
Level
developer
Location
src/dm/interface/dm.c
Implementations
DMComputeL2GradientDiff_Plex(DM dm, PetscReal time, PetscErrorCode (**funcs) in src/dm/impls/plex/plexfem.c
Index of all DM routines
Table of Contents for all manual pages
Index of all manual pages