SGBT02(3)

💅 SGBT02(3) 💅

Okay bestie, you're in the Library Functions Manual, on page sgbt02.f(3). It's giving LAPACK test-routine energy, and we're gonna get through every detail together. 🫶

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🌸 NAME 🌸

/home/abuild/rpmbuild/BUILD/lapack-static-3.12.0-build/lapack-3.12.0/TESTING/LIN/sgbt02.f

That's the NAME, no cap. Literally the whole path. 💀

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✨ SYNOPSIS ✨

Functions/Subroutines

       subroutine SGBT02 (trans, m, n, kl, ku, nrhs, a, lda, x, ldx, b, ldb,
           rwork, resid)

SGBT02

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💖 Function/Subroutine Documentation 💖

       subroutine SGBT02 (character trans, integer m, integer n, integer kl,
           integer ku, integer nrhs, real, dimension( lda, * ) a, integer lda,
           real, dimension( ldx, * ) x, integer ldx, real, dimension( ldb, * ) b,
           integer ldb, real, dimension( * ) rwork, real resid)

SGBT02

🎯 Purpose 🎯

Bestie, SGBT02 computes the residual for a solution of a banded system of equations op(A)*X = B:

RESID = norm(B - op(A)*X) / ( norm(op(A)) * norm(X) * EPS ),

where op(A) = A or A**T, depending on TRANS, and EPS is the machine epsilon. The norm used is the 1-norm. Periodt. ✨

🧮 Parameters 🧮

• TRANS — TRANS is CHARACTER*1. Specifies the form of the system of equations: = 'N': A * X = B (No transpose); = 'T': A**T * X = B (Transpose); = 'C': A**H * X = B (Conjugate transpose = Transpose).
• M — M is INTEGER. The number of rows of the matrix A. M >= 0.
• N — N is INTEGER. The number of columns of the matrix A. N >= 0.
• KL — KL is INTEGER. The number of subdiagonals within the band of A. KL >= 0.
• KU — KU is INTEGER. The number of superdiagonals within the band of A. KU >= 0.
• NRHS — NRHS is INTEGER. The number of columns of B. NRHS >= 0.
• A — A is REAL array, dimension (LDA,N). The original matrix A in band storage, stored in rows 1 to KL+KU+1.
• LDA — LDA is INTEGER. The leading dimension of the array A. LDA >= max(1,KL+KU+1).
• X — X is REAL array, dimension (LDX,NRHS). The computed solution vectors for the system of linear equations.
• LDX — LDX is INTEGER. The leading dimension of the array X. If TRANS = 'N', LDX >= max(1,N); if TRANS = 'T' or 'C', LDX >= max(1,M).
• B — B is REAL array, dimension (LDB,NRHS). On entry, the right hand side vectors for the system of linear equations. On exit, B is overwritten with the difference B - A*X.
• LDB — LDB is INTEGER. The leading dimension of the array B. IF TRANS = 'N', LDB >= max(1,M); if TRANS = 'T' or 'C', LDB >= max(1,N).
• RWORK — RWORK is REAL array, dimension (MAX(1,LRWORK)), where LRWORK >= M when TRANS = 'T' or 'C'; otherwise, RWORK is not referenced.
• RESID — RESID is REAL. The maximum over the number of right hand sides of norm(B - op(A)*X) / ( norm(op(A)) * norm(X) * EPS ).

👑 Author 👑

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

Definition at line 147 of file sgbt02.f.

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👑 Author 👑

Generated automatically by Doxygen for LAPACK from the source code.

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Footer vibes, bestie: LAPACK Version 3.12.0 — page path /home/abui...IN/sgbt02.f(3). That's the whole manual page, and it ate. 💅✨