SRC/zhfrk.f(3)

okay so this is the SRC/zhfrk.f(3) page from the Library Functions Manual, and it's giving level-3 BLAS main character energy for RFP-format matrices πŸ’…βœ¨

πŸ’– NAME πŸ’–

SRC/zhfrk.f

that's the whole name, bestie β€” short, sweet, and iconic πŸŽ€

✨ SYNOPSIS ✨

🧚 Functions/Subroutines 🧚

subroutine zhfrk (transr, uplo, trans, n, k, alpha, a, lda, beta, c)

ZHFRK performs a Hermitian rank-k operation for matrix in RFP format.

πŸ› οΈ Function/Subroutine Documentation πŸ› οΈ

subroutine zhfrk (character transr, character uplo, character trans, integer n, integer k, double precision alpha, complex*16, dimension( lda, * ) a, integer lda, double precision beta, complex*16, dimension( * ) c)

ZHFRK performs a Hermitian rank-k operation for matrix in RFP format.

🌟 Purpose 🌟

okay so this is a Level 3 BLAS like routine for C in RFP Format. Not me being dramatic β€” that's literally the description, bestie.

ZHFRK performs one of the Hermitian rank--k operations:

C := alpha*A*A**H + beta*C,

or

C := alpha*A**H*A + beta*C,

where alpha and beta are real scalars, C is an n--by--n Hermitian matrix and A is an n--by--k matrix in the first case and a k--by--n matrix in the second case.

πŸŽ€ Parameters πŸŽ€

πŸ’… TRANSR

TRANSR is CHARACTER*1. The options are giving:

  • = 'N': the Normal Form of RFP A is stored.
  • = 'C': the Conjugate-transpose Form of RFP A is stored.

πŸ’… UPLO

UPLO is CHARACTER*1. On entry, UPLO specifies whether the upper or lower triangular part of the array C is to be referenced, like this:

  • UPLO = 'U' or 'u' β€” only the upper triangular part of C is to be referenced.
  • UPLO = 'L' or 'l' β€” only the lower triangular part of C is to be referenced.

Unchanged on exit.

πŸ’… TRANS

TRANS is CHARACTER*1. On entry, TRANS specifies the operation to be performed:

  • TRANS = 'N' or 'n' β€” C := alpha*A*A**H + beta*C.
  • TRANS = 'C' or 'c' β€” C := alpha*A**H*A + beta*C.

Unchanged on exit.

πŸ’… N

N is INTEGER. On entry, N specifies the order of the matrix C. N must be at least zero. Unchanged on exit.

πŸ’… K

K is INTEGER. On entry with TRANS = 'N' or 'n', K specifies the number of columns of the matrix A, and on entry with TRANS = 'C' or 'c', K specifies the number of rows of the matrix A. K must be at least zero. Unchanged on exit.

πŸ’… ALPHA

ALPHA is DOUBLE PRECISION. On entry, ALPHA specifies the scalar alpha. Unchanged on exit.

πŸ’… A

A is COMPLEX*16 array, dimension (LDA,ka) β€” where KA is K when TRANS = 'N' or 'n', and is N otherwise. Before entry with TRANS = 'N' or 'n', the leading N--by--K part of the array A must contain the matrix A, otherwise the leading K--by--N part of the array A must contain the matrix A. Unchanged on exit.

πŸ’… LDA

LDA is INTEGER. On entry, LDA specifies the first dimension of A as declared in the calling (sub) program. When TRANS = 'N' or 'n' then LDA must be at least max( 1, n ), otherwise LDA must be at least max( 1, k ). Unchanged on exit.

πŸ’… BETA

BETA is DOUBLE PRECISION. On entry, BETA specifies the scalar beta. Unchanged on exit.

πŸ’… C

C is COMPLEX*16 array, dimension (N*(N+1)/2). On entry, the matrix A in RFP Format. RFP Format is described by TRANSR, UPLO and N. Note that the imaginary parts of the diagonal elements need not be set, they are assumed to be zero, and on exit they are set to zero.

πŸ‘‘ Author πŸ‘‘

  • Univ. of Tennessee
  • Univ. of California Berkeley
  • Univ. of Colorado Denver
  • NAG Ltd.

Definition at line 166 of file zhfrk.f.

πŸ‘‘ Author (auto-generated) πŸ‘‘

Generated automatically by Doxygen for LAPACK from the source code.


that's the whole page, bestie. It's from LAPACK version 3.12.0 and it lives at SRC/zhfrk.f(3) β€” no date in the footer, just iconic minimalism πŸ’…πŸ«Ά

πŸ“¦ where this page comes from