ZGBTRS(3)

💅 ZGBTRS(3) — Library Functions Manual 💅

okay bestie, welcome to the manual page for zgbtrs.f(3) — yes, that's the title — and it lives in the Library Functions Manual. The header path is literally /home/abui...RC/zgbtrs.f(3), no cap. This is the LAPACK zone, and this whole page is about the ZGBTRS subroutine. 🫶

👑 NAME 👑

The name/path on this page is exactly:

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

That's the source file this page is documenting, periodt. 💖

✨ SYNOPSIS ✨

🎀 Functions/Subroutines 🎀

       subroutine ZGBTRS (trans, n, kl, ku, nrhs, ab, ldab, ipiv, b, ldb, info)
           ZGBTRS

🧚 Function/Subroutine Documentation 🧚

   subroutine ZGBTRS (character trans, integer n, integer kl, integer ku,
       integer nrhs, complex*16, dimension( ldab, * ) ab, integer ldab,
       integer, dimension( * ) ipiv, complex*16, dimension( ldb, * ) b, integer
       ldb, integer info)
       ZGBTRS

💖 Purpose 💖

ZGBTRS solves a system of linear equations

A * X = B,  A**T * X = B,  or  A**H * X = B

with a general band matrix A using the LU factorization computed by ZGBTRF. That's the whole vibe, and honestly? iconic. ✨

🌸 Parameters 🌸

• TRANS — TRANS is CHARACTER*1 and it specifies the form of the system of equations. The values are:
  • 'N' — A * X = B (No transpose)
  • 'T' — A**T * X = B (Transpose)
  • 'C' — A**H * X = B (Conjugate transpose)
• N — N is INTEGER; it's the order of the matrix A. Constraint: N >= 0. 💯
• KL — KL is INTEGER; the number of subdiagonals within the band of A. Constraint: KL >= 0.
• KU — KU is INTEGER; the number of superdiagonals within the band of A. Constraint: KU >= 0.
• NRHS — NRHS is INTEGER; the number of right hand sides, i.e., the number of columns of the matrix B. Constraint: NRHS >= 0.
• AB — AB is COMPLEX*16 array, dimension (LDAB,N). Details of the LU factorization of the band matrix A, as computed by ZGBTRF. U is stored as an upper triangular band matrix with KL+KU superdiagonals in rows 1 to KL+KU+1, and the multipliers used during the factorization are stored in rows KL+KU+2 to 2*KL+KU+1.
• LDAB — LDAB is INTEGER; the leading dimension of the array AB. Constraint: LDAB >= 2*KL+KU+1.
• IPIV — IPIV is INTEGER array, dimension (N). The pivot indices; for 1 <= i <= N, row i of the matrix was interchanged with row IPIV(i).
• B — B is COMPLEX*16 array, dimension (LDB,NRHS). On entry, the right hand side matrix B. On exit, the solution matrix X.
• LDB — LDB is INTEGER; the leading dimension of the array B. Constraint: LDB >= max(1,N).
• INFO — INFO is INTEGER. = 0: successful exit. < 0: if INFO = -i, the i-th argument had an illegal value.

Author

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

Definition at line 136 of file zgbtrs.f.

🦋 Author 🦋

Generated automatically by Doxygen for LAPACK from the source code.

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xoxo bestie, this page is from LAPACK, Version 3.12.0, and the footer path is /home/abui...RC/zgbtrs.f(3). Slay. 💖✨