ZPTTRS(3)

okay so this is ZPTTRS(3) from the Library Functions Manual, and bestie, it’s giving “LAPACK tridiagonal solver realness” 💅✨

💖 NAME

/home/abuild/rpmbuild/BUILD/lapack-static-3.12.0-build/lapack-3.12.0/SRC/zpttrs.f — that’s the file, no cap 🫶

✨ SYNOPSIS

🧚 Functions/Subroutines

       subroutine ZPTTRS (uplo, n, nrhs, d, e, b, ldb, info)

and the main character is literally ZPTTRS 👑

🎀 Function/Subroutine Documentation

   subroutine ZPTTRS (character uplo, integer n, integer nrhs, double
       precision, dimension( * ) d, complex*16, dimension( * ) e, complex*16,
       dimension( ldb, * ) b, integer ldb, integer info)

yup, that’s ZPTTRS again — iconic 💫

🦋 Purpose:

ZPTTRS 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 ZPTTRF. 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. ✨

💜 Parameters

• UPLO is CHARACTER*1 — tells us the form of the factorization and whether E is the superdiagonal of the upper bidiagonal factor U or the subdiagonal of the lower bidiagonal factor L. = 'U': A = U**H *D*U, E is the superdiagonal of U; = 'L': A = L*D*L**H, E is the subdiagonal of L 🌸
• N is INTEGER — the order of the tridiagonal matrix A. N >= 0. 👑
• NRHS is INTEGER — the number of right hand sides, i.e., the number of columns of the matrix B. NRHS >= 0. 🫶
• D is DOUBLE PRECISION 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 is COMPLEX*16 array, dimension (N-1) — if UPLO = 'U', the (n-1) superdiagonal elements of the unit bidiagonal factor U from the factorization A = U**H*D*U. If UPLO = 'L', the (n-1) subdiagonal elements of the unit bidiagonal factor L from the factorization A = L*D*L**H. 🦋
• B is COMPLEX*16 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 is INTEGER — the leading dimension of the array B. LDB >= max(1,N). ⭐
• INFO is INTEGER — = 0: successful exit; < 0: if INFO = -k, the k-th argument had an illegal value. 💀

👑 Author

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

📌 Definition at line 120 of file zpttrs.f.

Definition at line 120 of file zpttrs.f. — periodt 💅

👑 Author

Generated automatically by Doxygen for LAPACK from the source code. 🫶

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okay that’s the whole vibe: signed off by LAPACK Version 3.12.0 and the footer source path /home/abui...RC/zpttrs.f(3) — and the date slot is empty in this source, so no fake date from me, bestie 💖✨