BLAS/SRC/cher2.f(3)

💖 BLAS/SRC/cher2.f 💖

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✨ NAME ✨

BLAS/SRC/cher2.f — it's giving hermitian rank 2 update, and it's giving it HARD 💅

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🌸 SYNOPSIS 🌸

Functions/Subroutines

• subroutine cher2 (uplo, n, alpha, x, incx, y, incy, a, lda) — CHER2, the main character 👑

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🦋 Function/Subroutine Documentation 🦋

subroutine cher2 (character uplo, integer n, complex alpha, complex, dimension(*) x, integer incx, complex, dimension(*) y, integer incy, complex, dimension(lda,*) a, integer lda)

CHER2

so like. what does she DO. let me tell you.

Purpose:

CHER2 performs the hermitian rank 2 operation

A := alpha*x*y**H + conjg( alpha )*y*x**H + A,

where alpha is a scalar, x and y are n element vectors and A is an n by n hermitian matrix. no cap, that's the whole vibe 🔥

Parameters

• UPLO — UPLO is CHARACTER*1. on entry, UPLO specifies whether the upper or lower triangular part of the array A is to be referenced, as follows:
  • UPLO = 'U' or 'u' — Only the upper triangular part of A is to be referenced.
  • UPLO = 'L' or 'l' — Only the lower triangular part of A is to be referenced.
• N — N is INTEGER. on entry, N specifies the order of the matrix A. N must be at least zero. (zero is fine bestie, we don't judge 🙈)
• ALPHA — ALPHA is COMPLEX. on entry, ALPHA specifies the scalar alpha. that's it, that's the girl 💜
• X — X is COMPLEX array, dimension at least ( 1 + ( n - 1 )*abs( INCX ) ). before entry, the incremented array X must contain the n element vector x.
• INCX — INCX is INTEGER. on entry, INCX specifies the increment for the elements of X. INCX must not be zero. 🚫
• Y — Y is COMPLEX array, dimension at least ( 1 + ( n - 1 )*abs( INCY ) ). before entry, the incremented array Y must contain the n element vector y.
• INCY — INCY is INTEGER. on entry, INCY specifies the increment for the elements of Y. INCY must not be zero. 🚫
• A — A is COMPLEX array, dimension ( LDA, N ).
  • Before entry with UPLO = 'U' or 'u', the leading n by n upper triangular part of the array A must contain the upper triangular part of the hermitian matrix and the strictly lower triangular part of A is not referenced. On exit, the upper triangular part of the array A 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 A must contain the lower triangular part of the hermitian matrix and the strictly upper triangular part of A is not referenced. On exit, the lower triangular part of the array A is overwritten by the lower triangular part of the updated matrix.
  • Note that 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. (they get zeroed out, periodt 💀)
• LDA — LDA is INTEGER. on entry, LDA specifies the first dimension of A as declared in the calling (sub) program. LDA must be at least max( 1, n ).

Author

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

Further Details:

• Level 2 Blas routine.
• -- Written on 22-October-1986.
  • Jack Dongarra, Argonne National Lab.
  • Jeremy Du Croz, Nag Central Office.
  • Sven Hammarling, Nag Central Office.
  • Richard Hanson, Sandia National Labs.

Definition at line 149 of file cher2.f. 🎀

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👑 Author 👑

Generated automatically by Doxygen for LAPACK from the source code. (the robots did this one, we just made it cute 💅)

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and that's the whole page bestie!! Version 3.12.0, dated Tue Nov 28 2023 12:08:41 — shoutout to BLAS/SRC/cher2.f(3) for being iconic, we're obsessed, mwah 🫶✨💖