CGTTRS(3)

CGTTRS(3) 🎀

okay so bestie, welcome to the Library Functions Manual — this whole page is about the file at /home/abuild/rpmbuild/BUILD/lapack-static-3.12.0-build/lapack-3.12.0/SRC/cgttrs.f, and the shorthand header/footer path is /home/abui...RC/cgttrs.f(3). no cap, we're doing LAPACK things. 💅

🌸 NAME 🌸

The NAME is literally the source file path:

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

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✨ SYNOPSIS ✨

Functions/Subroutines

subroutine CGTTRS (trans, n, nrhs, dl, d, du, du2, ipiv, b, ldb, info)
    CGTTRS

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💖 Function/Subroutine Documentation 💖

subroutine CGTTRS (character trans, integer n, integer nrhs, complex,
    dimension( * ) dl, complex, dimension( * ) d, complex, dimension( * )
    du, complex, dimension( * ) du2, integer, dimension( * ) ipiv, complex,
    dimension( ldb, * ) b, integer ldb, integer info)
    CGTTRS

🎯 Purpose 🎯

okay so CGTTRS solves one of the systems of equations

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

with a tridiagonal matrix A using the LU factorization computed by CGTTRF. periodt. 💫

🧾 Parameters 🧾

• TRANS — CHARACTER*1. Tells you which form of the system of equations you're solving, bestie:
  • = 'N': A * X = B (No transpose)
  • = 'T': A**T * X = B (Transpose)
  • = 'C': A**H * X = B (Conjugate transpose)
• N — INTEGER. The order of the matrix A. 💅
• NRHS — INTEGER. The number of right hand sides, i.e., the number of columns of the matrix B. NRHS >= 0.
• DL — COMPLEX array, dimension (N-1). The (n-1) multipliers that define the matrix L from the LU factorization of A.
• D — COMPLEX array, dimension (N). The n diagonal elements of the upper triangular matrix U from the LU factorization of A.
• DU — COMPLEX array, dimension (N-1). The (n-1) elements of the first super-diagonal of U.
• DU2 — COMPLEX array, dimension (N-2). The (n-2) elements of the second super-diagonal of U.
• IPIV — INTEGER array, dimension (N). The pivot indices; for 1 <= i <= n, row i of the matrix was interchanged with row IPIV(i). IPIV(i) will always be either i or i+1; IPIV(i) = i indicates a row interchange was not required.
• B — COMPLEX array, dimension (LDB,NRHS). On entry, the matrix of right hand side vectors B. On exit, B is overwritten by the solution vectors X. 🫶
• LDB — INTEGER. The leading dimension of the array B. LDB >= max(1,N).
• INFO — INTEGER. Exit status tea:
  • = 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 136 of file cgttrs.f.

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🫶 Author 🫶

Generated automatically by Doxygen for LAPACK from the source code.

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okay bye bestie 💖 this page is LAPACK Version 3.12.0, footer path /home/abui...RC/cgttrs.f(3), and that's the whole vibe. slay. ✨