SLANST(3)

💖 SLANST(3) — LAPACK Library Functions Manual 💖

🌸 NAME 🌸

Bestie, the NAME here is literally the file location:

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

And the page header/footer both point at:

/home/abui...RC/slanst.f(3)

This is the LAPACK SLANST function, and it is about to serve real symmetric tridiagonal matrix norm realness. ✨

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✨ 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. 💅

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💅 FUNCTION/SUBROUTINE DOCUMENTATION 💅

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

Okay so 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. No cap. 🦋

🎀 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. That is the whole assignment, and it ate. 💖

🌈 Returns 🌈

SLANST returns:

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). Also important, bestie: 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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💖 cute sign-off: this page is from LAPACK, Version 3.12.0, and the footer path is /home/abui...RC/slanst.f(3). No separate date is shown on this page, bestie — that is the whole footer vibe. 🫶