/home/abui...SRC/chpr.f(3)

🌸 NAME 🌸

okay bestie, welcome to the Library Functions Manual — this page is /home/abui...SRC/chpr.f(3), and the NAME is literally the big path: /home/abuild/rpmbuild/BUILD/lapack-static-3.12.0-build/lapack-3.12.0/BLAS/SRC/chpr.f 💅

---

✨ SYNOPSIS ✨

🌟 Functions/Subroutines 🌟

• subroutine CHPR (uplo, n, alpha, x, incx, ap) — CHPR

---

💖 Function/Subroutine Documentation 💖

here's the whole signature, bestie, no cap:

   subroutine CHPR (character uplo, integer n, real alpha, complex,
       dimension(*) x, integer incx, complex, dimension(*) ap)
       CHPR

🎀 Purpose 🎀

okay so CHPR performs the hermitian rank 1 operation, and the way that formula ate is:

A := alpha*x*x**H + A,

where alpha is a real scalar, x is an n element vector, and A is an n by n hermitian matrix, supplied in packed form. periodt 💅

🦋 Parameters 🦋

• UPLO — UPLO is CHARACTER*1. On entry, UPLO specifies whether the upper or lower triangular part of the 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 — N is INTEGER. On entry, N specifies the order of the matrix A. N must be at least zero.
• ALPHA — ALPHA is REAL. On entry, ALPHA specifies the scalar alpha.
• 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.
• AP — AP is COMPLEX 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.

🌈 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 129 of file chpr.f.

---

👑 Author 👑

Generated automatically by Doxygen for LAPACK from the source code.

---

xoxo bestie, this was LAPACK Version 3.12.0, file path /home/abui...SRC/chpr.f(3) 💖🦋