SGBTRS(3)

🌸 NAME 🌸

Okay so this is the sgbtrs.f(3) page from the Library Functions Manual, and the source file is literally /home/abuild/rpmbuild/BUILD/lapack-static-3.12.0-build/lapack-3.12.0/SRC/sgbtrs.f. That’s the whole NAME moment, bestie. 🫶

✨ SYNOPSIS ✨

Functions/Subroutines

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

💖 Function/Subroutine Documentation 💖

Here’s the full signature, character-for-character, no edits, no games:

   subroutine SGBTRS (character trans, integer n, integer kl, integer ku,
       integer nrhs, real, dimension( ldab, * ) ab, integer ldab, integer,
       dimension( * ) ipiv, real, dimension( ldb, * ) b, integer ldb, integer
       info)
       SGBTRS

✨ Purpose ✨

SGBTRS solves a system of linear equations — specifically A * X = B or A**T * X = B — with a general band matrix A using the LU factorization computed by SGBTRF. That’s the whole purpose, and it ate. 💅

🎀 Parameters 🎀

• TRANS — is CHARACTER*1; it specifies the form of the system of equations:
  • 'N': A * X = B (No transpose)
  • 'T': A**T* X = B (Transpose)
  • 'C': A**T* X = B (Conjugate transpose = Transpose)
• N — is INTEGER; the order of the matrix A. N >= 0.
• KL — is INTEGER; the number of subdiagonals within the band of A. KL >= 0.
• KU — is INTEGER; the number of superdiagonals within the band of A. KU >= 0.
• NRHS — is INTEGER; the number of right hand sides, i.e., the number of columns of the matrix B. NRHS >= 0.
• AB — is REAL array, dimension (LDAB,N). Details of the LU factorization of the band matrix A, as computed by SGBTRF. 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 — is INTEGER; the leading dimension of the array AB. LDAB >= 2*KL+KU+1.
• 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 — is REAL array, dimension (LDB,NRHS). On entry, the right hand side matrix B. On exit, the solution matrix X.
• LDB — is INTEGER; the leading dimension of the array B. LDB >= max(1,N).
• 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 sgbtrs.f.

📜 Author 📜

Generated automatically by Doxygen for LAPACK from the source code.

💖 Footer sign-off, bestie: LAPACK Version 3.12.0, source/page footer /home/abui...RC/sgbtrs.f(3), and the page doesn’t print a separate date — so no fake date energy here. 🎀