SPPT02(3)

okay so welcome to the sppt02.f(3) manual page, bestie 💖 — Library Functions Manual energy, LAPACK corner, and honestly it's giving "we're about to check a residual." No cap.

🎀 NAME 🎀

/home/abuild/rpmbuild/BUILD/lapack-static-3.12.0-build/lapack-3.12.0/TESTING/LIN/sppt02.f — that's the whole file path, and this page is literally all about it. Periodt.

✨ SYNOPSIS ✨

🌈 Functions/Subroutines 🌈

• subroutine SPPT02 (uplo, n, nrhs, a, x, ldx, b, ldb, rwork, resid) — the subroutine flex. It is SPPT02, and yes the name is iconic in a very "LAPACK testing" way.
  • SPPT02 — that's the name again, bestie.

💅 Function/Subroutine Documentation 💅

   subroutine SPPT02 (character uplo, integer n, integer nrhs, real, dimension(
       * ) a, real, dimension( ldx, * ) x, integer ldx, real, dimension( ldb, *
       ) b, integer ldb, real, dimension( * ) rwork, real resid)
       SPPT02

okay so that's the whole typed-out signature, and the subroutine name is SPPT02. Slay.

🧚 Purpose 🧚

SPPT02 computes the residual in the solution of a symmetric system of linear equations A*x = b when packed storage is used for the coefficient matrix. The ratio computed is:

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

where EPS is the machine precision. That's the whole purpose, and it ate. 💅

🍓 Parameters 🍓

• UPLO — is CHARACTER*1. Specifies whether the upper or lower triangular part of the symmetric matrix A is stored:
  • = 'U': Upper triangular
  • = 'L': Lower triangular
• N — is INTEGER. The number of rows and columns of the matrix A. N >= 0.
• NRHS — is INTEGER. The number of columns of B, the matrix of right hand sides. NRHS >= 0.
• A — is REAL array, dimension (N*(N+1)/2). The original symmetric matrix A, stored as a packed triangular matrix.
• X — is REAL array, dimension (LDX,NRHS). The computed solution vectors for the system of linear equations.
• LDX — is INTEGER. The leading dimension of the array X. LDX >= max(1,N).
• 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 — is INTEGER. The leading dimension of the array B. LDB >= max(1,N).
• RWORK — is REAL array, dimension (N).
• RESID — is REAL. The maximum over the number of right hand sides of norm(B - A*X) / ( norm(A) * norm(X) * EPS ).

👑 Author 👑

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

Definition at line 120 of file sppt02.f.

🌈 Author 🌈

Generated automatically by Doxygen for LAPACK from the source code.

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okay that's the whole page, bestie! Footer vibe check: LAPACK Version 3.12.0, and the path down there is /home/abui...IN/sppt02.f(3) — mwah 💋✨