rocsparse_sbsrilu0 Interface Reference

rocsparse_sbsrilu0 Interface Reference#

HIPFORT API Reference: hipfort_rocsparse::rocsparse_sbsrilu0 Interface Reference
hipfort_rocsparse::rocsparse_sbsrilu0 Interface Reference

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

Public Member Functions

integer(kind(rocsparse_status_success)) function rocsparse_sbsrilu0_ (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_sbsrilu0_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_sbsrilu0_rank_1 (handle, dir, mb, nnzb, descr, bsr_val, bsr_row_ptr, bsr_col_ind, block_dim, myinfo, policy, temp_buffer)
 

Detailed Description

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

rocsparse_bsrilu0 computes the incomplete LU factorization with 0 fill-ins and no pivoting of a sparse \(mb \times mb\) BSR matrix \(A\), such that

\[ A \approx LU \]

Computing the above incomplete LU factorization requires three steps to complete. First, determine the size of the required temporary storage buffer by calling rocsparse_Xbsrilu0_buffer_size(). After this buffer size has been determined, allocate the buffer and pass it to rocsparse_Xbsrilu0_analysis(). This will perform analysis on the sparsity pattern of the matrix. Finally, call rocsparse_sbsrilu0, rocsparse_dbsrilu0, rocsparse_cbsrilu0, or rocsparse_zbsrilu0 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_Xbsrilu0() are complete, the temporary buffer can be deallocated.

rocsparse_bsrilu0 reports the first zero pivot (either numerical or structural zero). The zero pivot status can be obtained by calling rocsparse_bsrilu0_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 nnzb*block_dim*block_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_successthe operation completed successfully.
rocsparse_status_invalid_handlethe library context was not initialized.
rocsparse_status_invalid_sizemb, nnzb, or block_dim is invalid.
rocsparse_status_invalid_pointerdescr, bsr_val, bsr_row_ptr, or bsr_col_ind pointer is invalid.
rocsparse_status_arch_mismatchthe device is not supported.
rocsparse_status_internal_erroran internal error occurred.
rocsparse_status_not_implementedrocsparse_matrix_type != rocsparse_matrix_type_general.
Example
Consider the sparse \(m \times m\) matrix \(A\), stored in the BSR storage format. The following example computes the incomplete LU factorization \(M \approx LU\) and solves the preconditioned system \(My = x\).

Member Function/Subroutine Documentation

◆ rocsparse_sbsrilu0_()

integer(kind(rocsparse_status_success)) function hipfort_rocsparse::rocsparse_sbsrilu0::rocsparse_sbsrilu0_ ( type(c_ptr), value  handle,
integer(kind(rocsparse_direction_row)), value  dir,
integer(c_int), value  mb,
integer(c_int), value  nnzb,
type(c_ptr), value  descr,
type(c_ptr), value  bsr_val,
type(c_ptr), value  bsr_row_ptr,
type(c_ptr), value  bsr_col_ind,
integer(c_int), value  block_dim,
type(c_ptr), value  myinfo,
integer(kind(rocsparse_solve_policy_auto)), value  policy,
type(c_ptr), value  temp_buffer 
)

◆ rocsparse_sbsrilu0_rank_0()

integer(kind(rocsparse_status_success)) function hipfort_rocsparse::rocsparse_sbsrilu0::rocsparse_sbsrilu0_rank_0 ( type(c_ptr)  handle,
integer(kind(rocsparse_direction_row))  dir,
integer(c_int)  mb,
integer(c_int)  nnzb,
type(c_ptr)  descr,
real(c_float), target  bsr_val,
integer(c_int), target  bsr_row_ptr,
integer(c_int), target  bsr_col_ind,
integer(c_int)  block_dim,
type(c_ptr)  myinfo,
integer(kind(rocsparse_solve_policy_auto))  policy,
type(c_ptr)  temp_buffer 
)

◆ rocsparse_sbsrilu0_rank_1()

integer(kind(rocsparse_status_success)) function hipfort_rocsparse::rocsparse_sbsrilu0::rocsparse_sbsrilu0_rank_1 ( type(c_ptr)  handle,
integer(kind(rocsparse_direction_row))  dir,
integer(c_int)  mb,
integer(c_int)  nnzb,
type(c_ptr)  descr,
real(c_float), dimension(:), target  bsr_val,
integer(c_int), dimension(:), target  bsr_row_ptr,
integer(c_int), dimension(:), target  bsr_col_ind,
integer(c_int)  block_dim,
type(c_ptr)  myinfo,
integer(kind(rocsparse_solve_policy_auto))  policy,
type(c_ptr)  temp_buffer 
)

The documentation for this interface was generated from the following file: