potrf_batch (USM Strided Version)#
Computes the Cholesky factorizations of a batch of symmetric (or
Hermitian, for complex data) positive-definite matrices. This routine
belongs to the oneapi::mkl::lapack namespace.
Description#
The routine forms the Cholesky factorizations of a symmetric
positive-definite or, for complex data, Hermitian positive-definite
matrices Ai, iϵ{1...batch_size}:
Ai =UiT *Ui for real data,Ai =UiH *Ui for complex data. ifuplo = mkl::uplo::upper,Ai =LiT *Li for real data,Ai =LiH *Li for complex data ifuplo = mkl::uplo::lower
Where Li is a lower triangular matrix and
Ui is an upper triangular matrix.
API#
Syntax#
namespace oneapi::mkl::lapack {
sycl::event potrf_batch(sycl::queue &queue,
mkl::uplo uplo,
int64_t n,
T *a,
int64_t lda,
int64_t stride_a,
int64_t batch_size,
T *scratchpad,
int64_t scratchpad_size,
const std::vector<sycl::event> &events = {})
}
This function supports the following precisions and devices:
T |
Devices supported |
|---|---|
|
CPU and GPU |
|
CPU and GPU |
|
CPU and GPU |
|
CPU and GPU |
Input Parameters#
- queue
Device queue where calculations will be performed.
- uplo
Indicates whether the upper or lower triangular part of
Ai is stored and howAi is factored:If uplo = mkl::uplo::upper, the array
astores the upper triangular parts of the matricesAi.If uplo = mkl::uplo::lower, the array
astores the lower triangular parts of the matricesAi.- n
Specifies the order of the matrices
Ai, (n ≥ 0).- a
Array containing a batch of input matrices
Ai, each ofAi being of sizelda*nand holding either upper or lower triangular parts of the matricesAi (see uplo).- lda
The leading dimension of
Ai (lda≥max(1, n)).- stride_a
The stride between the beginnings of matrices
Ai inside the batch (stride_a≥max(1, lda * n)).- batch_size
The number of problems in a batch (
batch_size≥ 0).- scratchpad
Scratchpad memory to be used by routine for storing intermediate results.
- scratchpad_size
Size of scratchpad memory as a number of floating point elements of type T. Size should not be less then the value returned by potrf_batch_scratchpad_size (Strided Version).
- events
List of events to wait for before starting computation. Defaults to empty list.
Output Parameters#
- a
The batch array
ais overwritten by the Cholesky factorUi orLi, as specified by uplo .
Exceptions#
Exception |
Description |
|---|---|
|
This exception is thrown when problems occur during calculations. You can obtain the info code of the problem using the info() method of the exception object: If If If |
Return Values#
Output event to wait on to ensure computation is complete.