Developer Reference for Intel® oneAPI Math Kernel Library for C

ID 766684
Date 3/22/2024
Public

A newer version of this document is available. Customers should click here to go to the newest version.

Document Table of Contents

mkl_sparse_?_trsv

Solves a system of linear equations for a triangular sparse matrix.

Syntax

sparse_status_t mkl_sparse_s_trsv (const sparse_operation_t operation, const float alpha, const sparse_matrix_t A, const struct matrix_descr descr, const float *x, float *y);

sparse_status_t mkl_sparse_d_trsv (const sparse_operation_t operation, const double alpha, const sparse_matrix_t A, const struct matrix_descr descr, const double *x, double *y);

sparse_status_t mkl_sparse_c_trsv (const sparse_operation_t operation, const MKL_Complex8 alpha, const sparse_matrix_t A, const struct matrix_descr descr, const MKL_Complex8 *x, MKL_Complex8 *y);

sparse_status_t mkl_sparse_z_trsv (const sparse_operation_t operation, const MKL_Complex16 alpha, const sparse_matrix_t A, const struct matrix_descr descr, const MKL_Complex16 *x, MKL_Complex16 *y);

Include Files

  • mkl_spblas.h

Description

The mkl_sparse_?_trsv routine solves a system of linear equations for a matrix:

op(A)*y = alpha * x
				

where A is a triangular sparse matrix , op is a matrix modifier for matrix A, alpha is a scalar, and x and y are vectors .

NOTE:

For sparse matrices in the BSR format, the supported combinations of (indexing,block_layout) are:

  • (SPARSE_INDEX_BASE_ZERO, SPARSE_LAYOUT_ROW_MAJOR)

  • (SPARSE_INDEX_BASE_ONE, SPARSE_LAYOUT_COLUMN_MAJOR)

Input Parameters

operation

Specifies operation op() on input matrix.

SPARSE_OPERATION_NON_TRANSPOSE

Non-transpose, op(A) = A.

SPARSE_OPERATION_TRANSPOSE

Transpose, op(A) = AT.

SPARSE_OPERATION_CONJUGATE_TRANSPOSE

Conjugate transpose, op(A) = AH.

alpha

Specifies the scalar alpha.

A

Handle which contains the input matrix A.

descr

Structure specifying sparse matrix properties.

sparse_matrix_type_t type - Specifies the type of a sparse matrix:

SPARSE_MATRIX_TYPE_GENERAL

The matrix is processed as is.

SPARSE_MATRIX_TYPE_SYMMETRIC

The matrix is symmetric (only the requested triangle is processed).

SPARSE_MATRIX_TYPE_HERMITIAN

The matrix is Hermitian (only the requested triangle is processed).

SPARSE_MATRIX_TYPE_TRIANGULAR

The matrix is triangular (only the requested triangle is processed).

SPARSE_MATRIX_TYPE_DIAGONAL

The matrix is diagonal (only diagonal elements are processed).

SPARSE_MATRIX_TYPE_BLOCK_TRIANGULAR

The matrix is block-triangular (only requested triangle is processed). Applies to BSR format only.

SPARSE_MATRIX_TYPE_BLOCK_DIAGONAL

The matrix is block-diagonal (only diagonal blocks are processed). Applies to BSR format only.

sparse_fill_mode_t mode - Specifies the triangular matrix part for symmetric, Hermitian, triangular, and block-triangular matrices:

SPARSE_FILL_MODE_LOWER

The lower triangular matrix part is processed.

SPARSE_FILL_MODE_UPPER

The upper triangular matrix part is processed.

sparse_diag_type_t diag - Specifies diagonal type for non-general matrices:

SPARSE_DIAG_NON_UNIT

Diagonal elements might not be equal to one.

SPARSE_DIAG_UNIT

Diagonal elements are equal to one.
x

Array of size at least m, where m is the number of rows of matrix A. On entry, the array must contain the vector x.

Output Parameters

y

Array of size at least m containing the solution to the system of linear equations.

Return Values

The function returns a 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.