SRC/dlapll.f(3)

📦
version 3.12.1 · 4 versions
, in arch rolling

💅 NAME 💅

SRC/dlapll.f — okay bestie, this is the SRC/dlapll.f(3) page from the Library Functions Manual, and it’s all about DLAPLL. DLAPLL measures the linear dependence of two vectors. That’s the vibe, periodt.

✨ SYNOPSIS ✨

🫶 Functions/Subroutines 🫶

       subroutine dlapll (n, x, incx, y, incy, ssmin)
           DLAPLL measures the linear dependence of two vectors.

🌸 Function/Subroutine Documentation 🌸

   subroutine dlapll (integer n, double precision, dimension( * ) x, integer
       incx, double precision, dimension( * ) y, integer incy, double precision
       ssmin)

DLAPLL measures the linear dependence of two vectors. Periodt. Keep reading for the whole breakdown 👑

🎀 Purpose 🎀

okay so bestie, given two column vectors X and Y, let

A = ( X Y ).

The subroutine first computes the QR factorization of A = Q*R, and then computes the SVD of the 2-by-2 upper triangular matrix R. The smaller singular value of R is returned in SSMIN, and that is used as the measurement of the linear dependency of the vectors X and Y. It’s giving linear-algebra main character energy, fr fr 🌈

💖 Parameters 💖

  • N — N is INTEGER. It’s the length of the vectors X and Y.
  • X — X is a DOUBLE PRECISION array, dimension (1+(N-1)*INCX). On entry, X contains the N-vector X. On exit, X is overwritten. (so yes, she gets changed, no cap 😭)
  • INCX — INCX is INTEGER. The increment between successive elements of X. INCX > 0.
  • Y — Y is a DOUBLE PRECISION array, dimension (1+(N-1)*INCY). On entry, Y contains the N-vector Y. On exit, Y is overwritten.
  • INCY — INCY is INTEGER. The increment between successive elements of Y. INCY > 0.
  • SSMIN — SSMIN is DOUBLE PRECISION. The smallest singular value of the N-by-2 matrix A = ( X Y ).

🌟 Author 🌟

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

Definition at line 101 of file dlapll.f.

👑 Author 👑

Generated automatically by Doxygen for LAPACK from the source code.

mwah 💋 this page is LAPACK, Version 3.12.0, and the source page is SRC/dlapll.f(3) — stay slay, bestie 🫶✨

📦 where this page comes from