getrf_batch (USM Strided Version)#
Computes the batch of LU factorizations of a batch of general m-by-n matrices.
This routine belongs to the oneapi::mkl::lapack namespace.
Description#
The routine computes the LU factorizations of a batch of general
m-by-n matrices Ai, as
Where Pi is a permutation matrix, Li is
lower triangular with unit diagonal elements (lower trapezoidal if
m > n) and Ui is upper triangular (upper trapezoidal
if m < n). The routine uses partial pivoting with row
interchanges.
API#
Syntax#
namespace oneapi::mkl::lapack {
sycl::event getrf_batch(sycl::queue &queue,
int64_t m,
int64_t n,
T *a,
int64_t lda,
int64_t stride_a,
int64_t *ipiv,
int64_t stride_ipiv,
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.
- m
The number of rows in the matrices
Ai (m ≥ 0).- n
The number of columns in the matrices
Ai (n ≥ 0).- a
Array holding input matrices
Ai.- lda
The leading dimension of
Ai (lda≥max(1, m)).- stride_a
The stride between the beginnings of matrices
Ai inside the batch arraya(stride_a≥max(1, lda * n)).- stride_ipiv
The stride between the beginnings of arrays
ipivi inside the arrayipiv(stride_ipiv≥max(1, min(m,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 than the value returned by getrf_batch_scratchpad_size (Strided Version).- events
List of events to wait for before starting computation. Defaults to empty list.
Output Parameters#
- a
Overwritten by
Li andUi. The unit diagonal elements ofLi are not stored.- ipiv
Array containing the batch of the pivot indices
ipivi each of size at leastmax(1,min(m,n)); for 1 ≤k≤min(m,n), rowkofAi was interchanged with rowipivi(k).
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.