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slapll.f(3)                         LAPACK                         slapll.f(3)

NAME
       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 (integerN, real, dimension( * )X, integerINCX, real,
       dimension( * )Y, integerINCY, realSSMIN)
       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:
           September 2012

       Definition at line 103 of file slapll.f.

Author
       Generated automatically by Doxygen for LAPACK from the source code.

Version 3.4.2                   Sat Nov 16 2013                    slapll.f(3)