ZHERK(3)

🎀 ZHERK(3) — Library Functions Manual 🎀

okay so bestie, this is the manual page for ZHERK, and yes it's from the Library Functions Manual. The source file lives at /home/abuild/rpmbuild/BUILD/lapack-static-3.12.0-build/lapack-3.12.0/BLAS/SRC/zherk.f — that whole path is also literally what the NAME section says, no cap. We're doing hermitian rank k updates and we're doing them with main character energy. 💅✨

🌸 NAME 🌸

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

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✨ SYNOPSIS ✨

🧚 Functions/Subroutines 🧚

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

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🦋 Function/Subroutine Documentation 🦋

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

🎯 Purpose 🎯

ZHERK 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. slay. 🦋

🌈 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**H + beta*C.
• TRANS = 'C' or 'c' — C := alpha*A**H*A + beta*C.

🎀 N

N is INTEGER. On entry, N specifies the order of the matrix C. N must be at least zero. no negativity allowed, bestie. 😌

🌸 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. periodt. 🫶

⭐ ALPHA

ALPHA is DOUBLE PRECISION. On entry, ALPHA specifies the scalar alpha. iconic scalar behavior. ✨

🧚 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 DOUBLE PRECISION. On entry, BETA specifies the scalar beta. another real scalar, another moment. 💜

👑 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 hermitian 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 hermitian 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.

Note bestie: 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. 💀✨

🍓 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 🧚

It's a 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.
• -- Modified 8-Nov-93 to set C(J,J) to DBLE( C(J,J) ) when BETA = 1.
  • Ed Anderson, Cray Research Inc.

Definition at line 172 of file zherk.f. 📍

Author 💫

Generated automatically by Doxygen for LAPACK from the source code.

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💖 okay that's the whole glow-up, bestie. This page is LAPACK Version 3.12.0 with footer path /home/abui...SRC/zherk.f(3) — and that's the tea. 🫶✨