Developer Reference for Intel® oneAPI Math Kernel Library for C

ID 766684
Date 3/22/2024
Public

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?tfttr

Copies a triangular matrix from the rectangular full packed format (TF) to the standard full format (TR) .

Syntax

lapack_int LAPACKE_stfttr (int matrix_layout , char transr , char uplo , lapack_int n , const float * arf , float * a , lapack_int lda );

lapack_int LAPACKE_dtfttr (int matrix_layout , char transr , char uplo , lapack_int n , const double * arf , double * a , lapack_int lda );

lapack_int LAPACKE_ctfttr (int matrix_layout , char transr , char uplo , lapack_int n , const lapack_complex_float * arf , lapack_complex_float * a , lapack_int lda );

lapack_int LAPACKE_ztfttr (int matrix_layout , char transr , char uplo , lapack_int n , const lapack_complex_double * arf , lapack_complex_double * a , lapack_int lda );

Include Files

  • mkl.h

Description

The routine copies a triangular matrix A from the Rectangular Full Packed (RFP) format to the standard full format. For the description of the RFP format, see Matrix Storage Schemes.

Input Parameters

matrix_layout

Specifies whether matrix storage layout is row major (LAPACK_ROW_MAJOR) or column major ( LAPACK_COL_MAJOR ).

transr

= 'N': arf is in the Normal format,

= 'T': arf is in the Transpose format (for stfttr and dtfttr),

= 'C': arf is in the Conjugate-transpose format (for ctfttr and ztfttr).

uplo

Specifies whether A is upper or lower triangular:

= 'U': A is upper triangular,

= 'L': A is lower triangular.

n

The order of the matrices arf and a. n 0.

arf

Array, size at least max (1, n*(n+1)/2).

On entry, the upper or lower triangular matrix A stored in the RFP format.
lda

The leading dimension of the array a. lda max(1,n).

Output Parameters

a

Array, size max(1,lda *n).

On exit, the triangular matrix A. If uplo = 'U', the leading n-by-n upper triangular part of the array a contains the upper triangular matrix, and the strictly lower triangular part of a is not referenced. If uplo = 'L', the leading n-by-n lower triangular part of the array a contains the lower triangular matrix, and the strictly upper triangular part of a is not referenced.

Return Values

This function returns a value info.

If info = 0, the execution is successful.

If info < 0, the i-th parameter had an illegal value.

If info = -1011, memory allocation error occurred.