DLAPTM(3)

💖 DLAPTM(3) — Library Functions Manual 💖

Okay so welcome to DLAPTM(3), bestie! This is from the Library Functions Manual, and the manual name is dlaptm.f(3). The header path thingy shows up as /home/abui...IN/dlaptm.f(3), which is giving build-artifact chic. This page is LAPACK, so we're doing symmetric tridiagonal matrix math. Slay.

📛 NAME

/home/abuild/rpmbuild/BUILD/lapack-static-3.12.0-build/lapack-3.12.0/TESTING/LIN/dlaptm.f

That's it. That's the NAME section. It's literally the source file path, no cap.

✨ SYNOPSIS ✨

📚 Functions/Subroutines 📚

• subroutine DLAPTM (n, nrhs, alpha, d, e, x, ldx, beta, b, ldb) — the main-character subroutine. Its name is DLAPTM.

🧚 Function/Subroutine Documentation 🧚

🌟 Full signature

subroutine DLAPTM (integer n, integer nrhs, double precision alpha, double precision, dimension( * ) d, double precision, dimension( * ) e, double precision, dimension( ldx, * ) x, integer ldx, double precision beta, double precision, dimension( ldb, * ) b, integer ldb)

Routine name: DLAPTM. Again. Because it's iconic like that.

🎯 Purpose

DLAPTM multiplies an N by NRHS matrix X by a symmetric tridiagonal matrix A and stores the result in a matrix B. The operation has the form

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

where alpha may be either 1. or -1. and beta may be 0., 1., or -1..

🧾 Parameters

N

N is INTEGER. It's the order of the matrix A, and the rule is N >= 0.

NRHS

NRHS is INTEGER. It's the number of right hand sides, i.e., the number of columns of the matrices X and B.

ALPHA

ALPHA is DOUBLE PRECISION. It's the scalar alpha. ALPHA must be 1. or -1.; otherwise, it is assumed to be 0. So don't be out here passing random vibes, okay?

D

D is a DOUBLE PRECISION array, dimension (N). It holds the n diagonal elements of the tridiagonal matrix A.

E

E is a DOUBLE PRECISION array, dimension (N-1). It holds the (n-1) subdiagonal or superdiagonal elements of A.

X

X is a DOUBLE PRECISION array, dimension (LDX,NRHS). It's the N by NRHS matrix X.

LDX

LDX is INTEGER. It's the leading dimension of the array X, and LDX >= max(N,1).

BETA

BETA is DOUBLE PRECISION. It's the scalar beta. BETA must be 0., 1., or -1.; otherwise, it is assumed to be 1. That's the rule, bestie.

B

B is a DOUBLE PRECISION array, dimension (LDB,NRHS). On entry, it's 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. It's the leading dimension of the array B, and LDB >= max(N,1).

👑 Author

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

Definition at line 115 of file dlaptm.f.

🪄 Author

Generated automatically by Doxygen for LAPACK from the source code.

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Okay final footer tea, bestie: this is LAPACK Version 3.12.0, source path /home/abui...IN/dlaptm.f(3), and there's no date printed in this footer to quote. Byeee 🫶💅✨