
DLAPLL(l) ) DLAPLL(l)
NAME
DLAPLL  two column vectors X and Y, let A = ( X Y )
SYNOPSIS
SUBROUTINE DLAPLL( N, X, INCX, Y, INCY, SSMIN )
INTEGER INCX, INCY, N
DOUBLE PRECISION SSMIN
DOUBLE PRECISION X( * ), Y( * )
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 2by2 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.
ARGUMENTS
N (input) INTEGER
The length of the vectors X and Y.
X (input/output) DOUBLE PRECISION array,
dimension (1+(N1)*INCX) On entry, X contains the Nvector X. On exit, X is over
written.
INCX (input) INTEGER
The increment between successive elements of X. INCX > 0.
Y (input/output) DOUBLE PRECISION array,
dimension (1+(N1)*INCY) On entry, Y contains the Nvector Y. On exit, Y is over
written.
INCY (input) INTEGER
The increment between successive elements of Y. INCY > 0.
SSMIN (output) DOUBLE PRECISION
The smallest singular value of the Nby2 matrix A = ( X Y ).
LAPACK version 3.0 15 June 2000 DLAPLL(l) 
