GVecSetBoundaryDifference

Applies the specified Dirichlet boundary conditions to this vector, but uses the difference of the value in the given vector and the computed value.

#include "gvec.h" 
int GVecSetBoundaryDifference(GVec v, GVec u, void *ctx)

v -The grid vector

u -A grid vector, usually the previous solution

ctx -An optional user provided context for the function