 LAPACK  3.4.2 LAPACK: Linear Algebra PACKage
slapll.f File Reference

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## Functions/Subroutines

subroutine slapll (N, X, INCX, Y, INCY, SSMIN)
SLAPLL measures the linear dependence of two vectors.

## Function/Subroutine Documentation

 subroutine slapll ( integer N, real, dimension( * ) X, integer INCX, real, dimension( * ) Y, integer INCY, real SSMIN )

SLAPLL measures the linear dependence of two vectors.

Purpose:
``` 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, which is used
as the measurement of the linear dependency of the vectors X and Y.```
Parameters:
 [in] N ``` N is INTEGER The length of the vectors X and Y.``` [in,out] X ``` X is REAL array, dimension (1+(N-1)*INCX) On entry, X contains the N-vector X. On exit, X is overwritten.``` [in] INCX ``` INCX is INTEGER The increment between successive elements of X. INCX > 0.``` [in,out] Y ``` Y is REAL array, dimension (1+(N-1)*INCY) On entry, Y contains the N-vector Y. On exit, Y is overwritten.``` [in] INCY ``` INCY is INTEGER The increment between successive elements of Y. INCY > 0.``` [out] SSMIN ``` SSMIN is REAL The smallest singular value of the N-by-2 matrix A = ( X Y ).```
Date:
September 2012

Definition at line 103 of file slapll.f.

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