# rocsolver_cungtr Interface Reference#

HIPFORT API Reference: hipfort_rocsolver::rocsolver_cungtr Interface Reference
hipfort_rocsolver::rocsolver_cungtr Interface Reference

UNGTR generates an n-by-n unitary Matrix Q. More...

## Public Member Functions

integer(kind(rocblas_status_success)) function rocsolver_cungtr_ (handle, uplo, n, A, lda, ipiv)

integer(kind(rocblas_status_success)) function rocsolver_cungtr_full_rank (handle, uplo, n, A, lda, ipiv)

integer(kind(rocblas_status_success)) function rocsolver_cungtr_rank_0 (handle, uplo, n, A, lda, ipiv)

integer(kind(rocblas_status_success)) function rocsolver_cungtr_rank_1 (handle, uplo, n, A, lda, ipiv)

## Detailed Description

UNGTR generates an n-by-n unitary Matrix Q.

Q is defined as the product of n-1 Householder reflectors of order n. If uplo indicates upper, then Q has the form

$Q = H_{n-1}H_{n-2}\cdots H_1$

On the other hand, if uplo indicates lower, then Q has the form

$Q = H_1H_2\cdots H_{n-1}$

The Householder matrices $$H_i$$ are never stored, they are computed from its corresponding Householder vectors $$v_i$$ and scalars $$\text{ipiv}[i]$$, as returned by HETRD in its arguments A and tau.

Parameters
 [in] handle rocblas_handle. [in] uplo rocblas_fill. Specifies whether the HETRD factorization was upper or lower triangular. If uplo indicates lower (or upper), then the upper (or lower) part of A is not used. [in] n rocblas_int. n >= 0. The number of rows and columns of the matrix Q. [in,out] A pointer to type. Array on the GPU of dimension lda*n. On entry, the Householder vectors as returned by HETRD. On exit, the computed matrix Q. [in] lda rocblas_int. lda >= m. Specifies the leading dimension of A. [in] ipiv pointer to type. Array on the GPU of dimension n-1. The Householder scalars as returned by HETRD.

## ◆ rocsolver_cungtr_()

 integer(kind(rocblas_status_success)) function hipfort_rocsolver::rocsolver_cungtr::rocsolver_cungtr_ ( type(c_ptr), value handle, integer(kind(rocblas_fill_upper)), value uplo, integer(c_int), value n, type(c_ptr), value A, integer(c_int), value lda, type(c_ptr), value ipiv )

## ◆ rocsolver_cungtr_full_rank()

 integer(kind(rocblas_status_success)) function hipfort_rocsolver::rocsolver_cungtr::rocsolver_cungtr_full_rank ( type(c_ptr) handle, integer(kind(rocblas_fill_upper)) uplo, integer(c_int) n, complex(c_float_complex), dimension(:,:), target A, integer(c_int) lda, complex(c_float_complex), dimension(:), target ipiv )

## ◆ rocsolver_cungtr_rank_0()

 integer(kind(rocblas_status_success)) function hipfort_rocsolver::rocsolver_cungtr::rocsolver_cungtr_rank_0 ( type(c_ptr) handle, integer(kind(rocblas_fill_upper)) uplo, integer(c_int) n, complex(c_float_complex), target A, integer(c_int) lda, complex(c_float_complex), target ipiv )

## ◆ rocsolver_cungtr_rank_1()

 integer(kind(rocblas_status_success)) function hipfort_rocsolver::rocsolver_cungtr::rocsolver_cungtr_rank_1 ( type(c_ptr) handle, integer(kind(rocblas_fill_upper)) uplo, integer(c_int) n, complex(c_float_complex), dimension(:), target A, integer(c_int) lda, complex(c_float_complex), dimension(:), target ipiv )

The documentation for this interface was generated from the following file: