rocsparse_sbsric0 Interface Reference

rocsparse_sbsric0 Interface Reference#

HIPFORT API Reference: hipfort_rocsparse::rocsparse_sbsric0 Interface Reference

Incomplete Cholesky factorization with 0 fill-ins and no pivoting using the BSR storage format. More...

Public Member Functions
integer(kind(rocsparse_status_success)) function	rocsparse_sbsric0_ (handle, dir, mb, nnzb, descr, bsr_val, bsr_row_ptr, bsr_col_ind, block_dim, myinfo, policy, temp_buffer)

integer(kind(rocsparse_status_success)) function	rocsparse_sbsric0_rank_0 (handle, dir, mb, nnzb, descr, bsr_val, bsr_row_ptr, bsr_col_ind, block_dim, myinfo, policy, temp_buffer)

integer(kind(rocsparse_status_success)) function	rocsparse_sbsric0_rank_1 (handle, dir, mb, nnzb, descr, bsr_val, bsr_row_ptr, bsr_col_ind, block_dim, myinfo, policy, temp_buffer)

Detailed Description

Incomplete Cholesky factorization with 0 fill-ins and no pivoting using the BSR storage format.

rocsparse_bsric0 computes the incomplete Cholesky factorization with 0 fill-ins and no pivoting of a sparse \(mb \times mb\) BSR matrix \(A\), such that

\[ A \approx LL^T \]

Computing the above incomplete Cholesky factorization requires three steps to complete. First, determine the size of the required temporary storage buffer by calling rocsparse_sbsric0_buffer_size, rocsparse_dbsric0_buffer_size, rocsparse_cbsric0_buffer_size, or rocsparse_zbsric0_buffer_size. After this buffer size has been determined, allocate the buffer and pass it to rocsparse_sbsric0_analysis, rocsparse_dbsric0_analysis, rocsparse_cbsric0_analysis, or rocsparse_zbsric0_analysis. This will perform analysis on the sparsity pattern of the matrix. Finally, call rocsparse_sbsric0, rocsparse_dbsric0, rocsparse_cbsric0, or rocsparse_zbsric0 to perform the actual factorization. The calculation of the buffer size and the analysis of the sparse matrix only need to be performed once for a given sparsity pattern, while the factorization can be repeatedly applied to multiple matrices having the same sparsity pattern. After all calls to rocsparse_Xbsric0() are complete, the temporary buffer can be deallocated.

rocsparse_bsric0 reports the first zero pivot (either numerical or structural zero). The zero pivot status can be obtained by calling rocsparse_bsric0_zero_pivot().

Note: This function is non-blocking and executed asynchronously with respect to the host. It can return before the actual computation has finished.; This routine supports execution in a hipGraph context.

Parameters

[in]	handle	- handle to the rocSPARSE library context queue.
[in]	dir	- direction that specified whether to count non-zero elements by `rocsparse_direction_row` or by `rocsparse_direction_column`.
[in]	mb	- number of block rows in the sparse BSR matrix.
[in]	nnzb	- number of non-zero block entries of the sparse BSR matrix.
[in]	descr	- descriptor of the sparse BSR matrix.
[in,out]	bsr_val	- array of length `nnzbblock_dimblock_dim` containing the values of the sparse BSR matrix.
[in]	bsr_row_ptr	- array of `mb+1` elements that point to the start of every block row of the sparse BSR matrix.
[in]	bsr_col_ind	- array of `nnzb` elements containing the block column indices of the sparse BSR matrix.
[in]	block_dim	- the block dimension of the BSR matrix. Between 1 and m, where `m=mb*block_dim`.
[in]	myInfo	- structure that holds the information collected during the analysis step.
[in]	policy	- `rocsparse_solve_policy_auto`.
[in]	temp_buffer	- temporary storage buffer allocated by the user.

Return values

rocsparse_status_success	the operation completed successfully.
rocsparse_status_invalid_handle	the library context was not initialized.
rocsparse_status_invalid_size	`mb`, `nnzb`, or `block_dim` is invalid.
rocsparse_status_invalid_pointer	`descr`, `bsr_val`, `bsr_row_ptr`, or `bsr_col_ind` pointer is invalid.
rocsparse_status_arch_mismatch	the device is not supported.
rocsparse_status_internal_error	an internal error occurred.
rocsparse_status_not_implemented	`rocsparse_matrix_type` != `rocsparse_matrix_type_general`.

Example: Consider the sparse \(m \times m\) matrix \(A\), stored in BSR storage format. The following example computes the incomplete Cholesky factorization \(M \approx LL^T\) and solves the preconditioned system \(My = x\).

Member Function/Subroutine Documentation