CLAGTM(3)

hii bestie 💖 welcome to the clagtm.f(3) page from the Library Functions Manual. It’s giving one very specific LAPACK routine, and we’re gonna go through every single detail, no skips, periodt. ✨

🎀 NAME 🎀

bestie, the official NAME here is literally this file path, so write it down exactly:

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

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✨ SYNOPSIS ✨

🧚 Functions/Subroutines 🧚

   subroutine CLAGTM (trans, n, nrhs, alpha, dl, d, du, x, ldx, beta, b,
       ldb)

CLAGTM performs a matrix-matrix product of the form C = αAB+βC, where A is a tridiagonal matrix, B and C are rectangular matrices, and α and β are scalars, which may be 0, 1, or -1. 💅

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💖 Function/Subroutine Documentation 💖

   subroutine CLAGTM (character trans, integer n, integer nrhs, real alpha,
       complex, dimension( * ) dl, complex, dimension( * ) d, complex,
       dimension( * ) du, complex, dimension( ldx, * ) x, integer ldx, real
       beta, complex, dimension( ldb, * ) b, integer ldb)

CLAGTM performs a matrix-matrix product of the form C = αAB+βC, where A is a tridiagonal matrix, B and C are rectangular matrices, and α and β are scalars, which may be 0, 1, or -1. No cap, that’s the whole vibe of this routine. 🦋

🎯 Purpose 🎯

okay so what it actually does: CLAGTM performs a matrix-matrix product of the form

B := alpha * A * X + beta * B

where A is a tridiagonal matrix of order N, B and X are N by NRHS matrices, and alpha and beta are real scalars, each of which may be 0., 1., or -1. 🔥

🧸 Parameters 🧸

• TRANS — TRANS is CHARACTER*1. Specifies the operation applied to A.
  • = 'N': No transpose, B := alpha * A * X + beta * B
  • = 'T': Transpose, B := alpha * A**T * X + beta * B
  • = 'C': Conjugate transpose, B := alpha * A**H * X + beta * B
• N — N is INTEGER. The order of the matrix A. N >= 0. 💖
• NRHS — NRHS is INTEGER. The number of right hand sides, i.e., the number of columns of the matrices X and B. ✨
• ALPHA — ALPHA is REAL. The scalar alpha. ALPHA must be 0., 1., or -1.; otherwise, it is assumed to be 0. 🫶
• DL — DL is COMPLEX array, dimension (N-1). The (n-1) sub-diagonal elements of T. 🌸
• D — D is COMPLEX array, dimension (N). The diagonal elements of T. 💜
• DU — DU is COMPLEX array, dimension (N-1). The (n-1) super-diagonal elements of T. 🦋
• X — X is COMPLEX array, dimension (LDX,NRHS). The N by NRHS matrix X. 🎀
• LDX — LDX is INTEGER. The leading dimension of the array X. LDX >= max(N,1). 💅
• BETA — BETA is REAL. The scalar beta. BETA must be 0., 1., or -1.; otherwise, it is assumed to be 1. 🌈
• B — B is COMPLEX array, dimension (LDB,NRHS). On entry, the N by NRHS matrix B. On exit, B is overwritten by the matrix expression B := alpha * A * X + beta * B. 🔥
• LDB — LDB is INTEGER. The leading dimension of the array B. LDB >= max(N,1). 👑

🫶 Author 🫶

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

Definition at line 143 of file clagtm.f. 📌

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🌸 Author 🌸

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

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mwah 💋 — footer facts, bestie: this is LAPACK Version 3.12.0 and the source path is /home/abui...RC/clagtm.f(3). That’s the whole page, slay. 🫶