int
hypre_StructMatrixInitializeShell( hypre_StructMatrix *matrix )
{
int ierr = 0;
hypre_StructGrid *grid;
hypre_StructStencil *user_stencil;
hypre_StructStencil *stencil;
hypre_Index *stencil_shape;
int stencil_size;
int num_values;
int *symm_elements;
int *num_ghost;
int extra_ghost[] = {0, 0, 0, 0, 0, 0};
hypre_BoxArray *data_space;
hypre_BoxArray *boxes;
hypre_Box *box;
hypre_Box *data_box;
int **data_indices;
int data_size;
int data_box_volume;
int i, j, d;
grid = hypre_StructMatrixGrid(matrix);
/*-----------------------------------------------------------------------
* Set up stencil and num_values:
* The stencil is a "symmetrized" version of the user's stencil
* as computed by hypre_StructStencilSymmetrize.
*
* The `symm_elements' array is used to determine what data is
* explicitely stored (symm_elements[i] < 0) and what data does is
* not explicitely stored (symm_elements[i] >= 0), but is instead
* stored as the transpose coefficient at a neighboring grid point.
*-----------------------------------------------------------------------*/
if (hypre_StructMatrixStencil(matrix) == NULL)
{
user_stencil = hypre_StructMatrixUserStencil(matrix);
hypre_StructStencilSymmetrize(user_stencil, &stencil, &symm_elements);
stencil_shape = hypre_StructStencilShape(stencil);
stencil_size = hypre_StructStencilSize(stencil);
if (!hypre_StructMatrixSymmetric(matrix))
{
/* store all element data */
for (i = 0; i < stencil_size; i++)
symm_elements[i] = -1;
num_values = stencil_size;
}
else
{
num_values = (stencil_size + 1) / 2;
}
hypre_StructMatrixStencil(matrix) = stencil;
hypre_StructMatrixSymmElements(matrix) = symm_elements;
hypre_StructMatrixNumValues(matrix) = num_values;
}
/*-----------------------------------------------------------------------
* Set ghost-layer size for symmetric storage
* - All stencil coeffs are to be available at each point in the
* grid, as well as in the user-specified ghost layer.
*-----------------------------------------------------------------------*/
num_ghost = hypre_StructMatrixNumGhost(matrix);
stencil = hypre_StructMatrixStencil(matrix);
stencil_shape = hypre_StructStencilShape(stencil);
stencil_size = hypre_StructStencilSize(stencil);
symm_elements = hypre_StructMatrixSymmElements(matrix);
for (i = 0; i < stencil_size; i++)
{
if (symm_elements[i] >= 0)
{
for (d = 0; d < 3; d++)
{
extra_ghost[2*d] =
hypre_max(extra_ghost[2*d], -hypre_IndexD(stencil_shape[i], d));
extra_ghost[2*d + 1] =
hypre_max(extra_ghost[2*d + 1], hypre_IndexD(stencil_shape[i], d));
}
}
}
for (d = 0; d < 3; d++)
{
num_ghost[2*d] += extra_ghost[2*d];
num_ghost[2*d + 1] += extra_ghost[2*d + 1];
}
/*-----------------------------------------------------------------------
* Set up data_space
*-----------------------------------------------------------------------*/
if (hypre_StructMatrixDataSpace(matrix) == NULL)
{
boxes = hypre_StructGridBoxes(grid);
data_space = hypre_BoxArrayCreate(hypre_BoxArraySize(boxes));
hypre_ForBoxI(i, boxes)
{
box = hypre_BoxArrayBox(boxes, i);
data_box = hypre_BoxArrayBox(data_space, i);
hypre_CopyBox(box, data_box);
for (d = 0; d < 3; d++)
{
hypre_BoxIMinD(data_box, d) -= num_ghost[2*d];
hypre_BoxIMaxD(data_box, d) += num_ghost[2*d + 1];
}
}
hypre_StructMatrix *
hypre_StructMatrixCreateMask( hypre_StructMatrix *matrix,
int num_stencil_indices,
int *stencil_indices )
{
hypre_StructMatrix *mask;
hypre_StructStencil *stencil;
hypre_Index *stencil_shape;
int stencil_size;
hypre_Index *mask_stencil_shape;
int mask_stencil_size;
hypre_BoxArray *data_space;
int **data_indices;
int **mask_data_indices;
int i, j;
stencil = hypre_StructMatrixStencil(matrix);
stencil_shape = hypre_StructStencilShape(stencil);
stencil_size = hypre_StructStencilSize(stencil);
mask = hypre_CTAlloc(hypre_StructMatrix, 1);
hypre_StructMatrixComm(mask) = hypre_StructMatrixComm(matrix);
hypre_StructGridRef(hypre_StructMatrixGrid(matrix),
&hypre_StructMatrixGrid(mask));
hypre_StructMatrixUserStencil(mask) =
hypre_StructStencilRef(hypre_StructMatrixUserStencil(matrix));
mask_stencil_size = num_stencil_indices;
mask_stencil_shape = hypre_CTAlloc(hypre_Index, num_stencil_indices);
for (i = 0; i < num_stencil_indices; i++)
{
hypre_CopyIndex(stencil_shape[stencil_indices[i]],
mask_stencil_shape[i]);
}
hypre_StructMatrixStencil(mask) =
hypre_StructStencilCreate(hypre_StructStencilDim(stencil),
mask_stencil_size,
mask_stencil_shape);
hypre_StructMatrixNumValues(mask) = hypre_StructMatrixNumValues(matrix);
hypre_StructMatrixDataSpace(mask) =
hypre_BoxArrayDuplicate(hypre_StructMatrixDataSpace(matrix));
hypre_StructMatrixData(mask) = hypre_StructMatrixData(matrix);
hypre_StructMatrixDataAlloced(mask) = 0;
hypre_StructMatrixDataSize(mask) = hypre_StructMatrixDataSize(matrix);
data_space = hypre_StructMatrixDataSpace(matrix);
data_indices = hypre_StructMatrixDataIndices(matrix);
mask_data_indices = hypre_CTAlloc(int *, hypre_BoxArraySize(data_space));
hypre_ForBoxI(i, data_space)
{
mask_data_indices[i] = hypre_TAlloc(int, num_stencil_indices);
for (j = 0; j < num_stencil_indices; j++)
{
mask_data_indices[i][j] = data_indices[i][stencil_indices[j]];
}
}
