slapll.f man page

slapll.f

Synopsis

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:

N

          N is INTEGER
          The length of the vectors X and Y.

X

          X is REAL array,
                         dimension (1+(N-1)*INCX)
          On entry, X contains the N-vector X.
          On exit, X is overwritten.

INCX

          INCX is INTEGER
          The increment between successive elements of X. INCX > 0.

Y

          Y is REAL 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 REAL
          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.

Date:

December 2016

Definition at line 104 of file slapll.f.

Author

Generated automatically by Doxygen for LAPACK from the source code.

Referenced By

The man page slapll(3) is an alias of slapll.f(3).

Tue Nov 14 2017 Version 3.8.0 LAPACK