CLANSY(3)

💅 CLANSY(3) — like, the clansy.f page, bestie ✨

okay so real talk, the manual name here is clansy.f(3) and the file it lives in is this whole journey:

/home/abuild/rpmbuild/BUILD/lapack-static-3.12.0-build/lapack-3.12.0/SRC/clansy.f

that's the whole NAME section, no cap. it's a Library Functions Manual situation. let's get into it 🫶

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✨ SYNOPSIS ✨

🦋 Functions/Subroutines

• real function CLANSY (norm, uplo, n, a, lda, work) — CLANSY returns the value of the 1-norm, or the Frobenius norm, or the infinity norm, or the element of largest absolute value of a complex symmetric matrix. that's the whole vibe 💖

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🎀 Function/Subroutine Documentation 🎀

⭐ the actual signature, literally

real function CLANSY (character norm, character uplo, integer n, complex,
    dimension( lda, * ) a, integer lda, real, dimension( * ) work)

CLANSY returns the value of the 1-norm, or the Frobenius norm, or the infinity norm, or the element of largest absolute value of a complex symmetric matrix. periodt 👑

🌸 Purpose:

!>
!> CLANSY  returns the value of the one norm,  or the Frobenius norm, or
!> the  infinity norm,  or the  element of  largest absolute value  of a
!> complex symmetric matrix A.
!>

like… it's giving "i measure matrices" and honestly? iconic 😌

🔥 Returns

CLANSY

!>
!>    CLANSY = ( max(abs(A(i,j))), NORM = 'M' or 'm'
!>             (
!>             ( norm1(A),         NORM = '1', 'O' or 'o'
!>             (
!>             ( normI(A),         NORM = 'I' or 'i'
!>             (
!>             ( normF(A),         NORM = 'F', 'f', 'E' or 'e'
!>
!> where  norm1  denotes the  one norm of a matrix (maximum column sum),
!> normI  denotes the  infinity norm  of a matrix  (maximum row sum) and
!> normF  denotes the  Frobenius norm of a matrix (square root of sum of
!> squares).  Note that  max(abs(A(i,j)))  is not a consistent matrix norm.
!>

⚠️ bestie, hear me: max(abs(A(i,j))) is not a consistent matrix norm. the source code said it, so i'm saying it. do not come for me 💀

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💜 Parameters 💜

• NORM — NORM is CHARACTER*1. specifies the value to be returned in CLANSY as described above. iykyk 🌈
• UPLO — UPLO is CHARACTER*1. specifies whether the upper or lower triangular part of the symmetric matrix A is to be referenced.
  • = 'U': upper triangular part of A is referenced
  • = 'L': lower triangular part of A is referenced
• N — N is INTEGER. the order of the matrix A. N >= 0. when N = 0, CLANSY is set to zero. zero matrix energy, we respect it 🧚
• A — A is COMPLEX array, dimension (LDA,N). 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. one triangle only, we're not reading both, that's the whole point 🎀
• LDA — LDA is INTEGER. the leading dimension of the array A. LDA >= max(N,1). respect the constraint or perish 🙈
• WORK — WORK is REAL array, dimension (MAX(1,LWORK)), where LWORK >= N when NORM = 'I' or '1' or 'O'; otherwise, WORK is not referenced. so if you're doing M or F norms, WORK is literally just sitting there, unbothered, moisturized, in its lane 💅

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👑 Author 👑

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

Definition at line 122 of file clansy.f. go look, it's right there 🔍

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🦋 Author (the other one) 🦋

Generated automatically by Doxygen for LAPACK from the source code. not a human, just a robot doing its little robot thing 🤖✨

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okay that's the whole page!! mwah 💖 and for the cute sign-off: this is LAPACK, Version 3.12.0, living over at /home/abui...RC/clansy.f(3) — slay, bye bestie 🫶🌸