/home/abui...RC/ssfrk.f(3)

🎀 NAME 🎀

/home/abuild/rpmbuild/BUILD/lapack-static-3.12.0-build/lapack-3.12.0/SRC/ssfrk.f — bestie, that's the whole path, yes the whole thing, it's giving "my filesystem has lore" 💅

This is a page from the Library Functions Manual, and the file in question lives at /home/abui...RC/ssfrk.f(3) — section 3, library functions, iykyk ✨

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🌸 SYNOPSIS 🌸

✨ Functions/Subroutines ✨

• subroutine SSFRK (transr, uplo, trans, n, k, alpha, a, lda, beta, c) — okay so SSFRK performs a symmetric rank-k operation for a matrix in RFP format. that's the whole vibe 🫶

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🦋 Function/Subroutine Documentation 🦋

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. periodt. 👑

💖 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.
!>

so like, level 3 BLAS energy but for C in RFP Format, and it does one of those two rank--k ops. literally both equations are right there, pick your fighter 🔥

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🌈 Parameters 🌈

💜 TRANSR

!>          TRANSR is CHARACTER*1
!>          = 'N':  The Normal Form of RFP A is stored;
!>          = 'T':  The Transpose Form of RFP A is stored.
!>

TRANSR is CHARACTER*1, and it's a whole choice: 'N' means the Normal Form of RFP A is stored, 'T' means the Transpose Form of RFP A is stored. that's it, that's the flag 🦋

🍓 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.
!>

UPLO is CHARACTER*1 and on entry it says which triangular half of the array C we're looking at: UPLO = 'U' or 'u' → only the upper triangular part of C is referenced, UPLO = 'L' or 'l' → only the lower triangular part of C is referenced. unchanged on exit, she does not get modified, respect her boundaries 🙈

🧚 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.
!>

TRANS is CHARACTER*1, on entry it picks the operation: TRANS = 'N' or 'n' gives you C := alpha*A*A**T + beta*C, and TRANS = 'T' or 't' gives you C := alpha*A**T*A + beta*C. also 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.
!>

N is INTEGER, it's the order of the matrix C, and N must be at least zero — no negative shenanigans, we don't do that here. 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.
!>

K is INTEGER. on entry with TRANS = 'N' or 'n', K is the number of columns of the matrix A; on entry with TRANS = 'T' or 't', K is the number of rows of the matrix A. and yeah, K must be at least zero. unchanged on exit 🫶

👑 ALPHA

!>          ALPHA is REAL
!>           On entry, ALPHA specifies the scalar alpha.
!>           Unchanged on exit.
!>

ALPHA is REAL, it's the scalar alpha, and it's unchanged on exit. iconic, stable, unbothered 🌸

💀 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.
!>

A is a 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, she's just there being data 🍓

🌈 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.
!>

LDA is INTEGER, the first dimension of A as declared in the calling (sub) program. when TRANS = 'N' or 'n', LDA must be at least max( 1, n ); otherwise LDA must be at least max( 1, k ). read it carefully bestie, the rule flips 😭 unchanged on exit.

💜 BETA

!>          BETA is REAL
!>           On entry, BETA specifies the scalar beta.
!>           Unchanged on exit.
!>

BETA is REAL, the scalar beta, unchanged on exit. twin of ALPHA, equally unbothered 💖

🦋 C

!>          C is REAL array, dimension (NT)
!>           NT = N*(N+1)/2. On entry, the symmetric matrix C in RFP
!>           Format. RFP Format is described by TRANSR, UPLO and N.
!>

C is a REAL array, dimension (NT) where NT = N*(N+1)/2. on entry it's the symmetric matrix C in RFP Format, and RFP Format is described by TRANSR, UPLO and N. don't ask me to draw it, just read TRANSR, UPLO and N 😌

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🧚 Author 🧚

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

Definition at line 164 of file ssfrk.f. ✨

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💅 Author 💅

Generated automatically by Doxygen for LAPACK from the source code. yes bestie, a robot wrote this page, and honestly? she ate 🤖💖

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and that's the whole page!! sign-off time: this was LAPACK, Version 3.12.0, footer-dated /home/abui...RC/ssfrk.f(3). mwah, go compute something symmetric 🔥👑💜