SRC/claqsy.f(3)

✨ NAME ✨

SRC/claqsy.f — that's the page, bestie. It lives in the Library Functions Manual, and it's about to give you the whole CLAQSY situation. 💅

---

💫 SYNOPSIS 💫

🌸 Functions/Subroutines 🌸

• subroutine claqsy (uplo, n, a, lda, s, scond, amax, equed) — CLAQSY scales a symmetric/Hermitian matrix, using scaling factors computed by spoequ. Slay. ✨

---

🧚 Function/Subroutine Documentation 🧚

Here's the full signature, character-for-character:

subroutine claqsy (character uplo, integer n, complex, dimension( lda, * ) a, integer lda, real, dimension( * ) s, real scond, real amax, character equed)

CLAQSY scales a symmetric/Hermitian matrix, using scaling factors computed by spoequ.

🎀 Purpose

CLAQSY equilibrates a symmetric matrix A using the scaling factors in the vector S. ✨

💖 Parameters

• UPLO — UPLO is CHARACTER*1. Specifies whether the upper or lower triangular part of the symmetric matrix A is stored.
  • = 'U': Upper triangular
  • = 'L': Lower triangular
• N — N is INTEGER. The order of the matrix A. N >= 0. 🫶
• A — A is COMPLEX array, dimension (LDA,N).
  • On entry, the symmetric matrix A. If UPLO = 'U', the leading n by n upper triangular part of A contains the upper triangular part of the matrix A, and the strictly lower triangular part of A is not referenced. If UPLO = 'L', the leading n by n lower triangular part of A contains the lower triangular part of the matrix A, and the strictly upper triangular part of A is not referenced.
  • On exit, if EQUED = 'Y', the equilibrated matrix: diag(S) * A * diag(S).
• LDA — LDA is INTEGER. The leading dimension of the array A. LDA >= max(N,1).
• S — S is REAL array, dimension (N). The scale factors for A. 🎀
• SCOND — SCOND is REAL. Ratio of the smallest S(i) to the largest S(i).
• AMAX — AMAX is REAL. Absolute value of largest matrix entry.
• EQUED — EQUED is CHARACTER*1. Specifies whether or not equilibration was done.
  • = 'N': No equilibration.
  • = 'Y': Equilibration was done, i.e., A has been replaced by diag(S) * A * diag(S).

🔮 Internal Parameters

• THRESH — threshold value used to decide if scaling should be done based on the ratio of the scaling factors. If SCOND < THRESH, scaling is done.
• LARGE and SMALL — threshold values used to decide if scaling should be done based on the absolute size of the largest matrix element. If AMAX > LARGE or AMAX < SMALL, scaling is done.

👑 Author

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

Definition at line 133 of file claqsy.f.

---

👑 Author 👑

Generated automatically by Doxygen for LAPACK from the source code.

---

That's the tea, bestie: LAPACK Version 3.12.0 on SRC/claqsy.f(3). Go forth and equilibrate something iconic. 💅✨🦋