rocsolver_ssygvd Interface Reference#
SYGVD computes the eigenvalues and (optionally) eigenvectors of a real generalized symmetric-definite eigenproblem. More...
Public Member Functions | |
integer(kind(rocblas_status_success)) function | rocsolver_ssygvd_ (handle, itype, evect, uplo, n, A, lda, B, ldb, D, E, myInfo) |
integer(kind(rocblas_status_success)) function | rocsolver_ssygvd_full_rank (handle, itype, evect, uplo, n, A, lda, B, ldb, D, E, myInfo) |
integer(kind(rocblas_status_success)) function | rocsolver_ssygvd_rank_0 (handle, itype, evect, uplo, n, A, lda, B, ldb, D, E, myInfo) |
integer(kind(rocblas_status_success)) function | rocsolver_ssygvd_rank_1 (handle, itype, evect, uplo, n, A, lda, B, ldb, D, E, myInfo) |
Detailed Description
SYGVD computes the eigenvalues and (optionally) eigenvectors of a real generalized symmetric-definite eigenproblem.
The problem solved by this function is either of the form
\[ \begin{array}{cl} A X = \lambda B X & \: \text{1st form,}\newline A B X = \lambda X & \: \text{2nd form, or}\newline B A X = \lambda X & \: \text{3rd form,} \end{array} \]
depending on the value of itype. The eigenvectors are computed using a divide-and-conquer algorithm, depending on the value of evect.
When computed, the matrix Z of eigenvectors is normalized as follows:
\[ \begin{array}{cl} Z^T B Z=I & \: \text{if 1st or 2nd form, or}\newline Z^T B^{-1} Z=I & \: \text{if 3rd form.} \end{array} \]
- Parameters
-
[in] handle rocblas_handle. [in] itype rocblas_eform.
Specifies the form of the generalized eigenproblem.[in] evect rocblas_evect.
Specifies whether the eigenvectors are to be computed. If evect is rocblas_evect_original, then the eigenvectors are computed. rocblas_evect_tridiagonal is not supported.[in] uplo rocblas_fill.
Specifies whether the upper or lower parts of the matrices A and B are stored. If uplo indicates lower (or upper), then the upper (or lower) parts of A and B are not used.[in] n rocblas_int. n >= 0.
The matrix dimensions.[in,out] A pointer to type. Array on the GPU of dimension lda*n.
On entry, the symmetric matrix A. On exit, if evect is original, the normalized matrix Z of eigenvectors. If evect is none, then the upper or lower triangular part of the matrix A (including the diagonal) is destroyed, depending on the value of uplo.[in] lda rocblas_int. lda >= n.
Specifies the leading dimension of A.[out] B pointer to type. Array on the GPU of dimension ldb*n.
On entry, the symmetric positive definite matrix B. On exit, the triangular factor of B as returned by POTRF.[in] ldb rocblas_int. ldb >= n.
Specifies the leading dimension of B.[out] D pointer to type. Array on the GPU of dimension n.
On exit, the eigenvalues in increasing order.[out] E pointer to type. Array on the GPU of dimension n.
This array is used to work internally with the tridiagonal matrix T associated with the reduced eigenvalue problem. On exit, if 0 < info <= n, it contains the unconverged off-diagonal elements of T (or properly speaking, a tridiagonal matrix equivalent to T). The diagonal elements of this matrix are in D; those that converged correspond to a subset of the eigenvalues (not necessarily ordered).[out] info pointer to a rocblas_int on the GPU.
If info = 0, successful exit. If info = j <= n and evect is rocblas_evect_none, j off-diagonal elements of an intermediate tridiagonal form did not converge to zero. If info = j <= n and evect is rocblas_evect_original, the algorithm failed to compute an eigenvalue in the submatrix from [j/(n+1), j/(n+1)] to [j%(n+1), j%(n+1)]. If info = n + j, the leading minor of order j of B is not positive definite.
Member Function/Subroutine Documentation
◆ rocsolver_ssygvd_()
integer(kind(rocblas_status_success)) function hipfort_rocsolver::rocsolver_ssygvd::rocsolver_ssygvd_ | ( | type(c_ptr), value | handle, |
integer(kind(rocblas_eform_ax)), value | itype, | ||
integer(kind(rocblas_evect_original)), value | evect, | ||
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 | B, | ||
integer(c_int), value | ldb, | ||
type(c_ptr), value | D, | ||
type(c_ptr), value | E, | ||
integer(c_int) | myInfo | ||
) |
◆ rocsolver_ssygvd_full_rank()
integer(kind(rocblas_status_success)) function hipfort_rocsolver::rocsolver_ssygvd::rocsolver_ssygvd_full_rank | ( | type(c_ptr) | handle, |
integer(kind(rocblas_eform_ax)) | itype, | ||
integer(kind(rocblas_evect_original)) | evect, | ||
integer(kind(rocblas_fill_upper)) | uplo, | ||
integer(c_int) | n, | ||
real(c_float), dimension(:,:), target | A, | ||
integer(c_int) | lda, | ||
real(c_float), dimension(:,:), target | B, | ||
integer(c_int) | ldb, | ||
real(c_float), dimension(:), target | D, | ||
real(c_float), dimension(:), target | E, | ||
integer(c_int) | myInfo | ||
) |
◆ rocsolver_ssygvd_rank_0()
integer(kind(rocblas_status_success)) function hipfort_rocsolver::rocsolver_ssygvd::rocsolver_ssygvd_rank_0 | ( | type(c_ptr) | handle, |
integer(kind(rocblas_eform_ax)) | itype, | ||
integer(kind(rocblas_evect_original)) | evect, | ||
integer(kind(rocblas_fill_upper)) | uplo, | ||
integer(c_int) | n, | ||
real(c_float), target | A, | ||
integer(c_int) | lda, | ||
real(c_float), target | B, | ||
integer(c_int) | ldb, | ||
real(c_float), target | D, | ||
real(c_float), target | E, | ||
integer(c_int) | myInfo | ||
) |
◆ rocsolver_ssygvd_rank_1()
integer(kind(rocblas_status_success)) function hipfort_rocsolver::rocsolver_ssygvd::rocsolver_ssygvd_rank_1 | ( | type(c_ptr) | handle, |
integer(kind(rocblas_eform_ax)) | itype, | ||
integer(kind(rocblas_evect_original)) | evect, | ||
integer(kind(rocblas_fill_upper)) | uplo, | ||
integer(c_int) | n, | ||
real(c_float), dimension(:), target | A, | ||
integer(c_int) | lda, | ||
real(c_float), dimension(:), target | B, | ||
integer(c_int) | ldb, | ||
real(c_float), dimension(:), target | D, | ||
real(c_float), dimension(:), target | E, | ||
integer(c_int) | myInfo | ||
) |
The documentation for this interface was generated from the following file: