SRC/slanst.f(3)

💅 SRC/slanst.f — Library Functions Manual 💅

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✨ NAME ✨

SRC/slanst.f

✨ SYNOPSIS ✨

🫶 Functions/Subroutines 🫶

• real function slanst (norm, n, d, e) — SLANST returns the value of the 1-norm, or the Frobenius norm, or the infinity norm, or the element of largest absolute value of a real symmetric tridiagonal matrix.

🌸 Function/Subroutine Documentation 🌸

real function slanst (character norm, integer n, real, dimension( * ) d, real, dimension( * ) e)

SLANST returns the value of the 1-norm, or the Frobenius norm, or the infinity norm, or the element of largest absolute value of a real symmetric tridiagonal matrix.

🎀 Purpose 🎀

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

💖 Returns 💖

SLANST

!>
!>    SLANST = ( 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.
!>

🦋 Parameters 🦋

NORM

NORM is CHARACTER*1. Specifies the value to be returned in SLANST as described above.

N

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

D

D is REAL array, dimension (N). The diagonal elements of A.

E

E is REAL array, dimension (N-1). The (n-1) sub-diagonal or super-diagonal elements of A.

👑 Author 👑

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

📍 Definition at line 99 of file slanst.f 📍

🌈 Author 🌈

Generated automatically by Doxygen for LAPACK from the source code.

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sign-off time, bestie: the footer credits LAPACK Version 3.12.0 and the source SRC/slanst.f(3) — no separate date is listed, so that's the whole timestamp vibe. 💜✨