trtrs (USM Version)#
Solves a system of linear equations with a triangular coefficient
matrix, with multiple right-hand sides. This routine belongs to the
oneapi::mkl::lapack namespace.
Description#
The routine solves for X the following systems of linear
equations with a triangular matrix A, with multiple right-hand
sides stored in B:
A*X = B |
if |
|
if |
AH |
if |
API#
Syntax#
namespace oneapi::mkl::lapack {
sycl::event trtrs(sycl::queue &queue,
mkl::uplo uplo,
mkl::transpose trans,
mkl::diag diag,
int64_t n,
int64_t nrhs,
const T *a,
int64_t lda,
T *b,
int64_t ldb,
T *scratchpad,
int64_t scratchpad_size,
const std::vector<sycl::event> &events = {})
}
trtrs (USM version) 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
Ais upper or lower triangular:If uplo =
uplo::upper, thenAis upper triangular.If uplo =
uplo::lower, thenAis lower triangular.- trans
If transa =
transpose::nontrans, thenA*X=Bis solved forX.If transa =
transpose::trans, thenAT*X=Bis solved forX.If transa =
transpose::conjtrans, thenAH*X=Bis solved forX.- diag
If diag =
diag::nonunit, thenAis not a unit triangular matrix.If diag =
diag::unit, thenAis unit triangular: diagonal elements ofAare assumed to be 1 and not referenced in the array a.- n
The order of
A; the number of rows inB;n ≥ 0.- nrhs
The number of right-hand sides; nrhs`` ≥ 0``.
- a
Array containing the matrix
A. The size ofamust be at leastlda*n.- lda
The leading dimension of
a;lda ≥ max(1, n).- b
Array containing the matrix
Bwhose columns are the right-hand sides for the systems of equations. The size ofbat leastldb*nrhs.- ldb
The leading dimension of b; ldb`` ≥ max(1, n)``.
- scratchpad
Pointer to scratchpad memory to be used by the 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 the trtrs_scratchpad_size function.- events
List of events to wait for before starting computation. Defaults to empty list.
Output Parameters#
- b
Overwritten by the solution matrix
X.
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 |
Return Values#
Output event to wait on to ensure computation is complete.