Developer Reference for Intel® oneAPI Math Kernel Library - C

Developer Reference

  • 0.9
  • 09/09/2020
  • Public Content
Contents

cluster_sparse_solver_get_csr_size

Computes the (local) number of rows and (local) number of nonzero entries for (distributed) CSR data corresponding to the provided name.

Syntax

void
cluster_sparse_solver_get_csr_size
(
_MKL_DSS_HANDLE_t
pt
,
_MKL_DSS_EXPORT_DATA
name
,
MKL_INT
*
local_nrows
,
MKL_INT
*
local_nnz
,
const int
*
comm
,
MKL_INT
*
error
);
Include Files
  • mkl_cluster_sparse_solver.h
Description
This routine uses the internal data created during the factorization phase of
cluster_sparse_solver
 for matrix
A
. The routine then:
  • Computes the local number of rows and the local number of nonzeros for CSR data that correspond to the provided
    name
  • Returns the computed values in
    local_nrows
     and
    local_nnz
It is assumed that the CSR data defined by the
name
 will be distributed in the same way as the matrix
A
 (as defined by
iparm
[39]
) used in
cluster_sparse_solver
.
The returned values can be used for allocating CSR arrays for factors
L
 and
U
, and also for allocating arrays for permutations
P
 and
Q
, or scaling matrix
D
 which can then be used with
cluster_sparse_solver_set_csr_ptrs
 or
cluster_sparse_solver_set_ptr
 for exporting corresponding data via
cluster_sparse_solver_export
.
Only call this routine after the factorization phase (
phase
=22
) of the
cluster_sparse_solver
 has been called. Neither
pt
, nor
iparm
 should be changed after the preceding call to
cluster_sparse_solver
.
Input Parameters
pt
Array with size of 64.
Handle to internal data structure used in the prior calls to
cluster_sparse_solver
.
Do not modify
pt
 after the calls to
cluster_sparse_solver
.
name
Specifies CSR data for which the output values are computed.
SPARSE_PTLUQT_L
Factor
L
 from
P
*
A
*
Q
=
L
*
U
.
SPARSE_PTLUQT_U
Factor
U
 from
P
*
A
*
Q
=
L
*
U
.
SPARSE_DPTLUQT_L
Factor
L
 from
P
* (
D
-1
A
)*
Q
=
L
*
U
.
SPARSE_DPTLUQT_U
Factor
U
 from
P
* (
D
-1
A
)*
Q
=
L
*
U
.
local_nrows
On entry, an array of size 1.
local_nnz
On entry, an array of size 1.
comm
MPI communicator. The solver uses the Fortran MPI communicator internally. Convert the MPI communicator to Fortran using the
MPI_Comm_c2f()
 function. See the examples in the
<install_dir>/examples
 directory.
Output Parameters
local_nrows
On output, the local number of rows for the CSR data which correspond to the
name
.
local_nnz
On output, the local number of nonzero entries for the CSR data which correspond to the
name
.
error
The error indicator:
error
Information
0
no error
-1
pt
 is a null pointer
-2
invalid
pt
-3
invalid
name
-4
unsupported
name
-9
unsupported internal code path, consider switching off non-default
iparm
 parameters for
cluster_sparse_solver
-10
unsupported case when the matrix
A
 is distributed among processes with overlap in the preceding calls to
cluster_sparse_solver
-12
internal memory error
Refer to
cl_solver_export_c.c
 for an example using this functionality.

Product and Performance Information

1

Intel's compilers may or may not optimize to the same degree for non-Intel microprocessors for optimizations that are not unique to Intel microprocessors. These optimizations include SSE2, SSE3, and SSSE3 instruction sets and other optimizations. Intel does not guarantee the availability, functionality, or effectiveness of any optimization on microprocessors not manufactured by Intel. Microprocessor-dependent optimizations in this product are intended for use with Intel microprocessors. Certain optimizations not specific to Intel microarchitecture are reserved for Intel microprocessors. Please refer to the applicable product User and Reference Guides for more information regarding the specific instruction sets covered by this notice.

Notice revision #20110804