ZSYRK(3)

💅 NAME 💅

okay so bestie, this is ZSYRK(3) from the Library Functions Manual — and the source file is literally:

/home/abuild/rpmbuild/BUILD/lapack-static-3.12.0-build/lapack-3.12.0/BLAS/SRC/zsyrk.f

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✨ SYNOPSIS ✨

🧚 Functions/Subroutines 🧚

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

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🦋 Function/Subroutine Documentation 🦋

subroutine ZSYRK (character uplo, character trans, integer n, integer k,
    complex*16 alpha, complex*16, dimension(lda,*) a, integer lda,
    complex*16 beta, complex*16, dimension(ldc,*) c, integer ldc)

and the star of the show is ZSYRK — iconic, honestly. 💅

🎯 Purpose 🎯

okay so here's the vibe: ZSYRK 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 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. 💖

🌈 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 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. 🦋

🌸 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.

🎀 N

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

🍓 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*16. On entry, ALPHA specifies the scalar alpha. main character scalar behavior, honestly. ✨

🧚 A

A is COMPLEX*16 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*16. On entry, BETA specifies the scalar beta. yes the other scalar, we love a duo. 😌

💎 C

C is COMPLEX*16 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 166 of file zsyrk.f.

📝 Author 📝

Generated automatically by Doxygen for LAPACK from the source code.

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mwah 💋 this one is LAPACK, Version 3.12.0, and the footer path is /home/abui...SRC/zsyrk.f(3) — bye bestie! 🎀✨