ZHPR2(3)

🦋 ZHPR2(3) — Library Functions Manual 🦋

okay bestie, welcome to the zhpr2.f(3) page from the Library Functions Manual 💅 this is the whole vibe, and yes we’re keeping every detail.

---

🎀 NAME 🎀

the source file is literally /home/abuild/rpmbuild/BUILD/lapack-static-3.12.0-build/lapack-3.12.0/BLAS/SRC/zhpr2.f — that’s the name, no cap 💖

✨ SYNOPSIS ✨

🧚 Functions/Subroutines 🧚

subroutine ZHPR2 (uplo, n, alpha, x, incx, y, incy, ap)
    ZHPR2

🔥 Function/Subroutine Documentation 🔥

here’s the full signature, bestie 🫶

subroutine ZHPR2 (character uplo, integer n, complex*16 alpha, complex*16,
       dimension(*) x, integer incx, complex*16, dimension(*) y, integer incy,
       complex*16, dimension(*) ap)
       ZHPR2

🌸 Purpose 🌸

okay so ZHPR2 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 supplied in packed form. periodt 💅

🛠️ Parameters 🛠️

• UPLO — is CHARACTER*1. On entry, UPLO specifies whether the upper or lower triangular part of matrix A is supplied in the packed array AP as follows:
  • UPLO = 'U' or 'u' — the upper triangular part of A is supplied in AP.
  • UPLO = 'L' or 'l' — the lower triangular part of A is supplied in AP.
• N — is INTEGER. On entry, N specifies the order of matrix A. N must be at least zero.
• ALPHA — is COMPLEX*16. On entry, ALPHA specifies the scalar alpha.
• X — is COMPLEX*16 array, dimension at least ( 1 + ( n - 1 )*abs( INCX ) ). Before entry, the incremented array X must contain the n element vector x.
• INCX — is INTEGER. On entry, INCX specifies the increment for the elements of X. INCX must not be zero.
• Y — is COMPLEX*16 array, dimension at least ( 1 + ( n - 1 )*abs( INCY ) ). Before entry, the incremented array Y must contain the n element vector y.
• INCY — is INTEGER. On entry, INCY specifies the increment for the elements of Y. INCY must not be zero.
• AP — is COMPLEX*16 array, dimension at least ( ( n*( n + 1 ) )/2 ).
  • Before entry with UPLO = 'U' or 'u', the array AP must contain the upper triangular part of the hermitian matrix packed sequentially, column by column, so that AP( 1 ) contains a( 1, 1 ), AP( 2 ) and AP( 3 ) contain a( 1, 2 ) and a( 2, 2 ) respectively, and so on. On exit, the array AP is overwritten by the upper triangular part of the updated matrix.
  • Before entry with UPLO = 'L' or 'l', the array AP must contain the lower triangular part of the hermitian matrix packed sequentially, column by column, so that AP( 1 ) contains a( 1, 1 ), AP( 2 ) and AP( 3 ) contain a( 2, 1 ) and a( 3, 1 ) respectively, and so on. On exit, the array AP 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. bestie do not forget this 💀

👑 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 144 of file zhpr2.f.

👑 Author 👑

Generated automatically by Doxygen for LAPACK from the source code. (iykyk, the page made itself ✨)

---

okay that’s the whole page 💖 brought to you by LAPACK Version 3.12.0 and /home/abui...SRC/zhpr2.f(3), with that 22-October-1986 date energy — mwah, slay, bye bestie 🫶✨