SRC/ssfrk.f(3)

✨ SRC/ssfrk.f ✨

okay so this is the SRC/ssfrk.f page from the Library Functions Manual, and it's literally the ssfrk moment: symmetric rank-k ops for a matrix in RFP format 💅. Let's unpack the whole thing, bestie.

🌸 NAME 🌸

SRC/ssfrk.f

🎀 SYNOPSIS 🎀

Functions/Subroutines

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

SSFRK performs a symmetric rank-k operation for matrix in RFP format. iconic.

💖 Function/Subroutine Documentation 💖

🧚 subroutine ssfrk

subroutine ssfrk (character transr, character uplo, character trans, integer
    n, integer k, real alpha, real, dimension( lda, * ) a, integer lda, real
    beta, real, dimension( * ) c)

SSFRK performs a symmetric rank-k operation for matrix in RFP format.

🔥 Purpose

Level 3 BLAS like routine for C in RFP Format.

SSFRK performs one of the symmetric rank--k operations

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

or

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

where alpha and beta are real scalars, C is an n--by--n symmetric matrix and A is an n--by--k matrix in the first case and a k--by--n matrix in the second case. math ate, no cap.

💅 Parameters

• TRANSR — TRANSR is CHARACTER*1. It's the RFP form selector, bestie:
  • = 'N': The Normal Form of RFP A is stored;
  • = 'T': The Transpose Form of RFP A is stored.
• UPLO — UPLO is CHARACTER*1. On entry, UPLO specifies whether the upper or lower triangular part of the array C is to be referenced as follows:
  • UPLO = 'U' or 'u' — Only the upper triangular part of C is to be referenced.
  • UPLO = 'L' or 'l' — Only the lower triangular part of C is to be referenced. Unchanged on exit.
• TRANS — TRANS is CHARACTER*1. On entry, TRANS specifies the operation to be performed as follows:
  • TRANS = 'N' or 'n' — C := alpha*A*A**T + beta*C.
  • TRANS = 'T' or 't' — C := alpha*A**T*A + beta*C. Unchanged on exit.
• N — N is INTEGER. On entry, N specifies the order of the matrix C. N must be at least zero. Unchanged on exit.
• 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 = 'T' or 't', K specifies the number of rows of the matrix A. K must be at least zero. Unchanged on exit.
• ALPHA — ALPHA is REAL. On entry, ALPHA specifies the scalar alpha. Unchanged on exit.
• A — A is REAL array, dimension (LDA,ka) 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.
• 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.
• BETA — BETA is REAL. On entry, BETA specifies the scalar beta. Unchanged on exit.
• C — C is REAL array, dimension (NT) where NT = N*(N+1)/2. On entry, the symmetric matrix C in RFP Format. RFP Format is described by TRANSR, UPLO and N.

🌟 Author

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

Definition at line 164 of file ssfrk.f.

👑 Author 👑

Generated automatically by Doxygen for LAPACK from the source code.

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and that's the whole page, bestie 🫶. Cute footer sign-off: source/version stamp is LAPACK Version 3.12.0, page stamp is SRC/ssfrk.f(3), and the date isn't separately spelled out on this copy — so no made-up date, periodt. 💖✨