CPTTS2(3)

✨ NAME ✨

hey bestie 💖 welcome to the cptts2.f(3) page — yes, that's the Library Functions Manual name folded in near the top, not a copy-pasted header line, okay? 🫶

• /home/abuild/rpmbuild/BUILD/lapack-static-3.12.0-build/lapack-3.12.0/SRC/cptts2.f — that's literally the file this manual page is about, periodt.

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🦋 SYNOPSIS 🦋

🧚 Functions/Subroutines

subroutine CPTTS2 (integer iuplo, integer n, integer nrhs, real, dimension(
       * ) d, complex, dimension( * ) e, complex, dimension( ldb, * ) b,
       integer ldb)

the synopsis caption says, and I quote: CPTTS2 solves a tridiagonal system of the form AX=B using the L D LH factorization computed by spttrf. ✨

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💅 Function/Subroutine Documentation 💅

subroutine CPTTS2 (integer iuplo, integer n, integer nrhs, real, dimension(
       * ) d, complex, dimension( * ) e, complex, dimension( ldb, * ) b,
       integer ldb)

CPTTS2 solves a tridiagonal system of the form AX=B using the L D LH factorization computed by spttrf. 🫶

🎀 Purpose 🎀

okay so the purpose block is short and iconic: CPTTS2 solves a tridiagonal system of the form

A * X = B

using the factorization A = U**H*D*U or A = L*D*L**H computed by CPTTRF. D is a diagonal matrix specified in the vector D, U (or L) is a unit bidiagonal matrix whose superdiagonal (subdiagonal) is specified in the vector E, and X and B are N by NRHS matrices. no cap, that's the whole vibe check 💜

🌸 Parameters 🌸

• IUPLO — IUPLO is INTEGER; it specifies the form of the factorization and whether the vector E is the superdiagonal of the upper bidiagonal factor U or the subdiagonal of the lower bidiagonal factor L.
  • = 1: A = U**H *D*U, E is the superdiagonal of U 🔥
  • = 0: A = L*D*L**H, E is the subdiagonal of L 🔥
• 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 factorization A = U**H *D*U or A = L*D*L**H. 🍓
• E — E is COMPLEX array, dimension (N-1); if IUPLO = 1, the (n-1) superdiagonal elements of the unit bidiagonal factor U from the factorization A = U**H*D*U. If IUPLO = 0, the (n-1) subdiagonal elements of the unit bidiagonal factor L from the factorization A = L*D*L**H. 🦋
• B — B is COMPLEX 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). 🌈

👑 Author 👑

the author squad is:

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

📌 Definition at line 112 of file cptts2.f.

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⭐ Author ⭐

Generated automatically by Doxygen for LAPACK from the source code.

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okay that's the whole page, bestie 💖 the footer-y sign-off is LAPACK / Version 3.12.0 plus the page path /home/abui...RC/cptts2.f(3) — cute sign-off, not a copied footer line. byeee 🎀✨