Computes size of scratchpad memory required for unmtr function.

Description

unmtr_scratchpad_size supports the following precisions.

T

std::complex<float>

std::complex<double>

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

Syntax

namespace oneapi::mkl::lapack {
template <typename T>
std::int64_t unmtr_scratchpad_size(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

queue

Device queue where calculations by unmtr function will be performed.

side

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

If side=side::left, $$Q$$ or $$Q^{H}$$ is applied to $$C$$ from the left.

If side=side::right, $$Q$$ or $$Q^{H}$$ 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 hetrd.

trans

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

If trans=transpose::nontrans, the routine multiplies $$C$$ by $$Q$$.

If trans=transpose::conjtrans, the routine multiplies $$C$$ by $$Q^{H}$$.

m

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

n

The number of columns the matrix $$C$$ ($$n \ge 0$$).

k

The number of elementary reflectors whose product defines the matrix $$Q$$ ($$0 \le k \le n$$).

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 unmtr function should be able to hold.