CSYRK(3)

💖 CSYRK(3) — LAPACK Library Functions Manual 💖

okay bestie, welcome to the CSYRK page — it's giving LAPACK library functions manual energy, and we're gonna read it together, no cap ✨

🌸 NAME 🌸

Bestie, this page is for /home/abuild/rpmbuild/BUILD/lapack-static-3.12.0-build/lapack-3.12.0/BLAS/SRC/csyrk.f. That's the whole name line, and yes it's a whole path — we love a dramatic entrance 💅

✨ SYNOPSIS ✨

🎀 Functions/Subroutines 🎀

subroutine CSYRK (uplo, trans, n, k, alpha, a, lda, beta, c, ldc)
    CSYRK

and yes, the routine's own name is literally CSYRK, main character energy 👑

🌟 Function/Subroutine Documentation 🌟

Here's the signature in full, bestie:

subroutine CSYRK (character uplo, character trans, integer n, integer k,
    complex alpha, complex, dimension(lda,*) a, integer lda, complex beta,
    complex, dimension(ldc,*) c, integer ldc)

CSYRK

🦋 Purpose 🦋

Okay so CSYRK performs one of the symmetric rank k operations, and it's giving:

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

or

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

where alpha and beta are 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. Periodt 💅

💅 Parameters 💅

🍓 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' — 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.

🦋 TRANS

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

• TRANS = 'N' or 'n' — C := alpha*A*A**T + beta*C.
• TRANS = 'T' or 't' — C := alpha*A**T*A + beta*C.

🌸 N

N is INTEGER. On entry, N specifies the order of the matrix C. N must be at least zero. Lowkey important 😌

🎀 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.

💜 ALPHA

ALPHA is COMPLEX. On entry, ALPHA specifies the scalar alpha.

🧚 A

A is COMPLEX 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.

🔥 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 ).

🌈 BETA

BETA is COMPLEX. On entry, BETA specifies the scalar beta.

👑 C

C is COMPLEX array, dimension ( LDC, N ). Before entry with UPLO = 'U' or 'u', the leading n by n upper triangular part of the array C must contain the upper triangular part of the symmetric matrix, and the strictly lower triangular part of C is not referenced. On exit, the upper triangular part of the array C is overwritten by the upper triangular part of the updated matrix.

Before entry with UPLO = 'L' or 'l', the leading n by n lower triangular part of the array C must contain the lower triangular part of the symmetric matrix, and the strictly upper triangular part of C is not referenced. On exit, the lower triangular part of the array C is overwritten by the lower triangular part of the updated matrix.

💖 LDC

LDC is INTEGER. On entry, LDC specifies the first dimension of C as declared in the calling (sub) program. LDC must be at least max( 1, n ).

🫶 Author 🫶

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

🔥 Further Details 🔥

Level 3 Blas routine.

• Written on 8-February-1989.
  • Jack Dongarra, Argonne National Laboratory.
  • Iain Duff, AERE Harwell.
  • Jeremy Du Croz, Numerical Algorithms Group Ltd.
  • Sven Hammarling, Numerical Algorithms Group Ltd.

⭐ Definition at line ⭐

Definition at line 166 of file csyrk.f.

🌈 Author (the auto-generated one) 🌈

Generated automatically by Doxygen for LAPACK from the source code.

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mwah 💋 — this page's footer says LAPACK Version 3.12.0 and points at /home/abui...SRC/csyrk.f(3). No date is printed in that footer, bestie, so I'm not making one up 😭🫶