Intel® oneAPI Math Kernel Library (oneMKL) - Data Parallel C++ Developer Reference

Developer Reference

Contents

getri_batch (Group Version)

Computes the batch of inverses of an LU-factored general matrices determined by the
getrf_batch
 (Group Version) function. This routine belongs to the
oneapi::mkl::lapack
 namespace.

Description

The routine computes the inverses
A
1
-1
 of a general matrices
A
1
,
iϵ{1...batch_size}
. Before calling this routine, call getrf_batch (Group Version) function to factorize
A
1
.
The total number of problems to solve,
batch_size
, is a sum of sizes of all of the groups of parameters as provided by
group_sizes
array.

API

Syntax
namespace oneapi::mkl::lapack {
  cl::sycl::event getri_batch(cl::sycl::queue &queue,
  std::int64_t *n,
  T **a,
  std::int64_t *lda,
  std::int64_t **ipiv,
  std::int64_t group_count,
  std::int64_t *group_sizes,
  T *scratchpad,
  std::int64_t scratchpad_size,
  const std::vector<cl::sycl::event> &events = {})
}
Function supports the following precisions and devices.
T
Devices supported
float
Host, CPU, and GPU
double
Host, CPU, and GPU
std::complex<float>
Host, CPU, and GPU
std::complex<double>
Host, CPU, and GPU
Input Parameters
queue
Device queue where calculations will be performed.
n
Array of
group_count
 parameters
n
g
 specifying the order of the matrices
A
i
 (0 ≤
n
g
) belonging to group
g
.
a
Result of the getrf_batch (Group Version) function
lda
Array of
group_count
 parameters lda
g
 specifying the leading dimension of
A
i
 (
n
g
 ≤ lda
g
) belonging to group
g
.
ipiv
The array as returned by getrf_batch (Group Version).
group_count
Specifies the number of groups of parameters. Must be at least 0.
group_sizes
Array of group_count integers. Array element with index
g
 specifies the number of problems to solve for each of the groups of parameters
g
. So the total number of problems to solve,
batch_size
, is a sum of all parameter group sizes.
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 getri_batch_scratchpad_size (Group Version).
events
List of events to wait for before starting computation. Defaults to empty list.
Output Parameters
a
Overwritten by the
n
g
-by-
n
g
 matrices
A
i
-1
.
Exceptions
Exception
Description
mkl::lapack::batch_exception
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
info = -n
, the
n
-th parameter had an illegal value.
If
info
 equals the value passed as scratchpad size, and detail() returns non-zero, then the passed scratchpad is of insufficient size, and the required size should be not less then value returned by the detail() method of the exception object.
Return Values
Output event to wait on to ensure computation is complete.

Product and Performance Information

1

Performance varies by use, configuration and other factors. Learn more at www.Intel.com/PerformanceIndex.