ZLANSP(3)

💅 ZLANSP(3) — Library Functions Manual, but make it cute 💅

okay so bestie, welcome to the Library Functions Manual page for ZLANSP(3). grab a lil snack 🍓 because we're about to make packed complex symmetric matrix norms make sense, no cap.

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🌸 NAME 🌸

the entire NAME section is literally just this path, and I mean literally:

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

that's it. that's the whole name. iconic minimalism 💅

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✨ SYNOPSIS ✨

Functions/Subroutines

double precision function ZLANSP (norm, uplo, n, ap, work)

ZLANSP returns the value of the 1-norm, or the Frobenius norm, or the infinity norm, or the element of largest absolute value of a symmetric matrix supplied in packed form.

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📚 Function/Subroutine Documentation 📚

double precision function ZLANSP (character norm, character uplo, integer n, complex*16, dimension( * ) ap, double precision, dimension( * ) work)

ZLANSP returns the value of the 1-norm, or the Frobenius norm, or the infinity norm, or the element of largest absolute value of a symmetric matrix supplied in packed form.

🎯 Purpose 🎯

the source says, and I quote with love:

!>
!> ZLANSP  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,  supplied in packed form.
!>

📦 Returns 📦

ZLANSP

!>
!>    ZLANSP = ( 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.
!>

aka: pick your norm, bestie, and ZLANSP gives you the answer. but note the little warning at the end — max(abs(A(i,j))) is not a consistent matrix norm. that's a real caveat, not me being dramatic 💀

🧸 Parameters 🧸

🌸 NORM 🌸

NORM is CHARACTER*1.

Specifies the value to be returned in ZLANSP as described above.

🦋 UPLO 🦋

UPLO is CHARACTER*1.

Specifies whether the upper or lower triangular part of the symmetric matrix A is supplied.

• = 'U': Upper triangular part of A is supplied
• = 'L': Lower triangular part of A is supplied

🎀 N 🎀

N is INTEGER.

The order of the matrix A. N >= 0. When N = 0, ZLANSP is set to zero.

🍓 AP 🍓

AP is COMPLEX*16 array, dimension (N*(N+1)/2).

The upper or lower triangle of the symmetric matrix A, packed columnwise in a linear array. The j-th column of A is stored in the array AP as follows:

if UPLO = 'U', AP(i + (j-1)*j/2) = A(i,j) for 1<=i<=j;
if UPLO = 'L', AP(i + (j-1)*(2n-j)/2) = A(i,j) for j<=i<=n.

🧚 WORK 🧚

WORK is DOUBLE PRECISION array, dimension (MAX(1,LWORK)), where LWORK >= N when NORM = 'I' or '1' or 'O'; otherwise, WORK is not referenced.

👑 Author 👑

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

Definition at line 114 of file zlansp.f.

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🌈 Author 🌈

Generated automatically by Doxygen for LAPACK from the source code.

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💌 cute lil sign-off: this page is from LAPACK Version 3.12.0, with the page tag /home/abui...RC/zlansp.f(3). there's no date line in the footer, bestie — that's all it gave us. mwah 💋✨