Developer Reference for Intel® oneAPI Math Kernel Library for C
mkl_?potrf_compact
Syntax
voidmkl_spotrf_compact ( MKL_LAYOUTlayout , MKL_UPLOuplo , MKL_INTn , float*ap , MKL_INTldap , MKL_INT*info , MKL_COMPACT_PACKformat , MKL_INTnm );
voidmkl_cpotrf_compact ( MKL_LAYOUTlayout , MKL_UPLOuplo , MKL_INTn , float*ap , MKL_INTldap , MKL_INT*info , MKL_COMPACT_PACKformat , MKL_INTnm );
voidmkl_dpotrf_compact ( MKL_LAYOUTlayout , MKL_UPLOuplo , MKL_INTn , double*ap , MKL_INTldap , MKL_INT*info , MKL_COMPACT_PACKformat , MKL_INTnm );
voidmkl_zpotrf_compact ( MKL_LAYOUTlayout , MKL_UPLOuplo , MKL_INTn , double*ap , MKL_INTldap , MKL_INT*info , MKL_COMPACT_PACKformat , MKL_INTnm );
Description
The routine forms the Cholesky factorization of a set of symmetric, positive definite (or, for complex data, Hermitian, positive-definite), n x n matrices A c , stored in Compact format, as:
A c = U cT *U c (for real data), A c = U cH *U c (for complex data), if uplo = MKL_UPPER
A c = L c *L cT (for real data), A c = L c *L cH (for complex data), if uplo = MKL_LOWER
where L c is a lower triangular matrix, and U c is upper triangular. The factorization (output) data will also be stored in Compact format.
Before calling this routine, call mkl_?gepack_compact to store the matrices in the Compact format.
Compact routines have some limitations; see Numerical Limitations .
Input Parameters
- layout
-
Specifies whether two-dimensional array storage is row-major ( MKL_ROW_MAJOR ) or column-major ( MKL_COL_MAJOR ).
- uplo
-
Must be MKL_UPPER or MKL_LOWER Indicates whether the upper or lower triangular part of A c has been stored and will be factored. If uplo = MKL_UPPER, the upper triangular part of A c is stored, and the strictly lower triangular part of A c is not referenced. If uplo = MKL_LOWER, the lower triangular part of A c is stored, and the strictly upper triangular part of A c is not referenced.
- n
-
The order of A c ; n >= 0.
- ldap
-
Column stride (column-major layout) or row stride (row-major layout) of A c .
- ap
-
Points to the beginning of the nm A c matrices. On entry, ap contains either the upper or the lower triangular part of A c (see uplo).
- format
-
Specifies the format of the compact matrices. See Compact Format or mkl_get_format_compact for details.
- nm
-
Total number of matrices stored in Compact format; nm >= 0.
Application Notes:
Before calling this routine, mkl_?gepack_compact must be called. After calling this routine, mkl_?geunpack_compact should be called, unless another compact routine will be called for the Compact format matrices.
The total number of floating-point operations is approximately nm * (1/3) n3 for real flavors and nm * (4/3) n3 for complex flavors.
Output Parameters
- ap
-
The upper or lower triangular part of A c , stored in Compact format in ap , is overwritten by its Cholesky factor U c or L c (as specified by uplo). ap now points to the beginning of this set of factors, stored in Compact format.
- info
-
The parameter is not currently used in this routine. It is reserved for the future use.