Developer Reference for Intel® oneAPI Math Kernel Library for Fortran

ID 766686
Date 10/31/2024
Public
Document Table of Contents

mkl_sparse_?_syrkd

Computes the product of sparse matrix with its transpose (or conjugate transpose) and stores the result as a dense matrix.

Syntax

stat = mkl_sparse_s_syrkd (operation, A, alpha, beta, C, layout, ldc)

stat = mkl_sparse_d_syrkd (operation, A, alpha, beta, C, layout, ldc)

stat = mkl_sparse_c_syrkd (operation, A, alpha, beta, C, layout, ldc)

stat = mkl_sparse_z_syrkd (operation, A, alpha, beta, C, layout, ldc)

Include Files

  • mkl_spblas.f90

Description

The mkl_sparse_?_syrkd routine performs a sparse matrix-matrix operation which results in a dense matrix C that is either symmetric (real case) or Hermitian (complex case):

C := beta*C + alpha*A*op(A)
or
C := beta*C + alpha*op(A)*A
depending on the matrix modifier op which can be the transpose for real matrices or conjugate transpose for complex matrices. Here, A is a sparse matrix and C is a dense matrix.

NOTE:
This routine is not supported for sparse matrices in COO or CSC formats. It supports only CSR and BSR formats. Additionally, this routine supports only the sorted CSR and sorted BSR formats for the input matrix. If data is unsorted, call the mkl_sparse_order routine before either mkl_sparse_syrk or mkl_sparse_?_syrkd.

Input Parameters

operation

C_INT.

Specifies the operation op() performed on the input matrix.

SPARSE_OPERATION_NON_TRANSPOSE, Non-transpose, C := beta*C + alpha*A*op(A) where op(*) is the transpose (real matrices) or conjugate transpose (complex matrices).

SPARSE_OPERATION_TRANSPOSE, Transpose,C := beta*C + alpha*AT*A for real matrix A.

SPARSE_OPERATION_CONJUGATE_TRANSPOSE Conjugate transpose,C := beta*C + alpha*AH*A for complex matrix A.

A

SPARSE_MATRIX_T.

Handle which contains the sparse matrix A.

alpha

C_FLOAT for mkl_sparse_s_syrkd

C_DOUBLE for mkl_sparse_d_syrkd

C_FLOAT_COMPLEX for mkl_sparse_c_syrkd

C_DOUBLE_COMPLEX for mkl_sparse_z_syrkd

Scalar parameter alpha.

beta

C_FLOAT for mkl_sparse_s_syrkd

C_DOUBLE for mkl_sparse_d_syrkd

C_FLOAT_COMPLEX for mkl_sparse_c_syrkd

C_DOUBLE_COMPLEX for mkl_sparse_z_syrkd

Scalar parameter beta.

layout

Describes the storage scheme for the dense matrix.

layout = SPARSE_LAYOUT_COLUMN_MAJOR

Storage of elements uses column-major layout.

layout = SPARSE_LAYOUT_ROW_MAJOR

Storage of elements uses row-major layout.
ldc

C_INT.

Leading dimension of matrix C.

NOTE:

Only the upper triangular part of matrix C is processed. Therefore, you must set real values of alpha and beta for complex matrices in order to obtain a Hermitian matrix.

Output Parameters

C

SPARSE_MATRIX_T.

Resulting dense matrix. Only the upper triangular part of the matrix is computed.

stat

INTEGER

Value indicating whether the operation was successful or not, and why:

SPARSE_STATUS_SUCCESS

The operation was successful.

SPARSE_STATUS_NOT_INITIALIZED

The routine encountered an empty handle or matrix array.

SPARSE_STATUS_ALLOC_FAILED

Internal memory allocation failed.

SPARSE_STATUS_INVALID_VALUE

The input parameters contain an invalid value.

SPARSE_STATUS_EXECUTION_FAILED

Execution failed.

SPARSE_STATUS_INTERNAL_ERROR

An error in algorithm implementation occurred.

SPARSE_STATUS_NOT_SUPPORTED

The requested operation is not supported.