ormtr_scratchpad_size

Computes size of scratchpad memory required for ormtr function.

Description

ormtr_scratchpad_size supports the following precisions.

T

float

double

Computes the number of elements of type T the scratchpad memory to be passed to ormtr function should be able to hold. Calls to this routine must specify the template parameter explicitly.

ormtr_scratchpad_size

Syntax

namespace oneapi::mkl::lapack {
  template <typename T>
  std::int64_t ormtr_scratchpad_size(cl::sycl::queue &queue, oneapi::mkl::side side, oneapi::mkl::uplo upper_lower, oneapi::mkl::transpose trans, std::int64_t m, std::int64_t n, std::int64_t lda, std::int64_t ldc)
}

Input Parameters

In the descriptions below, r denotes the order of \(Q\):

\(r = m\)

if side = side::left

\(r = n\)

if side = side::right

queue

Device queue where calculations by ormtr function will be performed.

side

Must be either side::left or side::right.

If side = side::left, \(Q\) or \(Q^{T}\) is applied to \(C\) from the left.

If side = side::right, \(Q\) or \(Q^{T}\) is applied to \(C\) from the right.

upper_lower

Must be either uplo::upper or uplo::lower. Uses the same upper_lower as supplied to sytrd.

trans

Must be either transpose::nontrans or transpose::trans.

If trans = transpose::nontrans, the routine multiplies \(C\) by \(Q\).

If trans = transpose::trans, the routine multiplies \(C\) by \(Q^{T}\).

m

The number of rows in the matrix \(C\) \((m \ge 0)\).

n

The number of rows in the matrix \(C\) \((n \ge 0)\).

lda

The leading dimension of a \((\max(1, r) \le \text{lda})\).

ldc

The leading dimension of c \((\max(1, n) \le \text{ldc})\).

Return Value

The number of elements of type T the scratchpad memory to be passed to ormtr function should be able to hold.

Parent topic: LAPACK Singular Value and Eigenvalue Problem Routines