mkl_sparse_?

Computes the QR decomposition for the matrix of a sparse linear system and calculates the solution.

Syntax

sparse_status_t mkl_sparse_d_qr ( sparse_operation_t operation, sparse_matrix_t A, struct matrix_descr descr, sparse_layout_t layout, MKL_INT columns, double *x, MKL_INT ldx, const double *b, MKL_INT ldb );

sparse_status_t mkl_sparse_s_qr ( sparse_operation_t operation, sparse_matrix_t A, struct matrix_descr descr, sparse_layout_t layout, MKL_INT columns, float *x, MKL_INT ldx, const float *b, MKL_INT ldb );

Include Files

mkl_sparse_qr.h

Description

The mkl_sparse_?_qr routine computes the QR decomposition for the matrix of a sparse linear system A*x = b, so that A = Q*R where Q is the orthogonal matrix and R is upper triangular, and calculates the solution.

Note

Currently, mkl_sparse_?_qr supports only square and overdetermined systems. For underdetermined systems you can manually transpose the system matrix and use QR decomposition for A^T to get the minimum-norm solution for the original underdetermined system.

Note

Currently, mkl_sparse_?_qr supports only CSR format for the input matrix, non-transpose operation, and single right-hand side.

Input Parameters

operation

Specifies the operation to perform.

Note

Currently, the only suppored value is SPARSE_OPERATION_NON_TRANSPOSE (non-transpose case; that is, A*x = b is solved).

A

Handle containing a sparse matrix in an internal data structure.

descr

Structure specifying sparse matrix properties. Only the parameters listed here are currently supported.

type

Specifies the type of sparse matrix.

Note

Currently, the only supported value is SPARSE_MATRIX_TYPE_GENERAL (the matrix is processed as-is).

layout

Describes the storage scheme for the dense matrix:

`SPARSE_LAYOUT_COLUMN_MAJOR`	Storage of elements uses column-major layout.
`SPARSE_LAYOUT_ROW_MAJOR`	Storage of elements uses row-major layout.

x

Array with a size of at least rows*cols:

	layout = `SPARSE_LAYOUT_COLUMN_MAJOR`	layout = `SPARSE_LAYOUT_ROW_MAJOR`
`rows` (number of rows in x)	ldx	Number of columns in A
`cols` (number of columns in x)	columns	ldx

columns

Number of columns in matrix b.

ldx

Specifies the leading dimension of matrix x.

b

Array with a size of at least rows*cols:

	layout = `SPARSE_LAYOUT_COLUMN_MAJOR`	layout = `SPARSE_LAYOUT_ROW_MAJOR`
`rows` (number of rows in b)	ldb	Number of columns in A
`cols` (number of columns in b)	columns	ldb

ldb

Specifies the leading dimension of matrix b.

Output Parameters

x: Overwritten by the updated matrix y.

Return Values

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.