SPTTRS(3)

💅 SPTTRS(3) — Library Functions Manual

okay bestie, welcome to the SPTTRS(3) page ✨ This one is from the Library Functions Manual, and it’s giving LAPACK main character energy. No cap, every technical detail below is the real deal.

✨ NAME ✨

This page is literally about:

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

That’s the file, periodt. 💅

🦋 SYNOPSIS 🦋

Functions/Subroutines

       subroutine SPTTRS (n, nrhs, d, e, b, ldb, info)
           SPTTRS

🧚 Function/Subroutine Documentation 🧚

The signature is right here, bestie — exact copy, no edits:

   subroutine SPTTRS (integer n, integer nrhs, real, dimension( * ) d, real,
       dimension( * ) e, real, dimension( ldb, * ) b, integer ldb, integer
       info)
       SPTTRS

🎀 Purpose 🎀

Okay so SPTTRS solves a tridiagonal system of the form

A * X = B

using the L*D*L**T factorization of A computed by SPTTRF. D is a diagonal matrix specified in the vector D, L is a unit bidiagonal matrix whose subdiagonal is specified in the vector E, and X and B are N by NRHS matrices. Slay. 🔥

🔥 Parameters 🔥

• N — N is INTEGER. The order of the tridiagonal matrix A. N >= 0. 👑
• NRHS — NRHS is INTEGER. The number of right hand sides, i.e., the number of columns of the matrix B. NRHS >= 0. ✨
• D — D is REAL array, dimension (N). The n diagonal elements of the diagonal matrix D from the L*D*L**T factorization of A. 🍓
• E — E is REAL array, dimension (N-1). The (n-1) subdiagonal elements of the unit bidiagonal factor L from the L*D*L**T factorization of A. E can also be regarded as the superdiagonal of the unit bidiagonal factor U from the factorization A = U**T*D*U. 🦋
• B — B is REAL array, dimension (LDB,NRHS). On entry, the right hand side vectors B for the system of linear equations. On exit, the solution vectors, X. 💖
• LDB — LDB is INTEGER. The leading dimension of the array B. LDB >= max(1,N). 🌸
• INFO — INFO is INTEGER.
  • = 0: successful exit
  • < 0: if INFO = -k, the k-th argument had an illegal value

💖 Author 💖

The author squad on this one:

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

Definition at line 108 of file spttrs.f. 🎀

🌸 Author 🌸

This page was generated automatically by Doxygen for LAPACK from the source code. No cap. 🤖✨

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Footer sign-off, bestie: LAPACK, Version 3.12.0, source path /home/abui...RC/spttrs.f(3). That’s the whole footer vibe — mwah 💋🫶