BLAS/SRC/ssyrk.f(3)

🌸 BLAS/SRC/ssyrk.f(3) — ssyrk has entered the chat 🌸

💖 NAME 💖

BLAS/SRC/ssyrk.f — bestie, this is the page for the ssyrk routine, the symmetric rank-k update one 💅

---

✨ SYNOPSIS ✨

🌟 Functions/Subroutines 🌟

• subroutine ssyrk (uplo, trans, n, k, alpha, a, lda, beta, c, ldc) — SSYRK

---

💖 Function/Subroutine Documentation 💖

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

SSYRK

🎯 Purpose

OK so SSYRK 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 — CHARACTER*1. On entry, UPLO tells us whether the upper or lower triangular part of the array C is the one being referenced, like choosing which side of the group chat to screenshot 🙈
  • 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 — CHARACTER*1. On entry, TRANS specifies the operation to be performed:
  • TRANS = 'N' or 'n' — C := alpha*A*A**T + beta*C.
  • TRANS = 'T' or 't' — C := alpha*A**T*A + beta*C.
  • TRANS = 'C' or 'c' — C := alpha*A**T*A + beta*C.
• N — INTEGER. On entry, N specifies the order of the matrix C. N must be at least zero, no cap 🫶
• K — INTEGER. On entry with TRANS = 'N' or 'n', K specifies the number of columns of the matrix A. On entry with TRANS = 'T' or 't' or 'C' or 'c', K specifies the number of rows of the matrix A. K must be at least zero.
• ALPHA — REAL. On entry, ALPHA specifies the scalar alpha ✨
• 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.
• LDA — 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 — REAL. On entry, BETA specifies the scalar beta 🎀
• C — REAL 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 — 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 168 of file ssyrk.f.

---

🫶 Author 🫶

Generated automatically by Doxygen for LAPACK from the source code.

---

okay bye bestie 💖 this page is stamped LAPACK Version 3.12.0, and the manual-page moment is BLAS/SRC/ssyrk.f(3) — that’s the footer source/version vibe, periodt ✨🫶💅