clapll (3) - Linux Man Pages

NAME

clapll.f -

SYNOPSIS


Functions/Subroutines


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

Function/Subroutine Documentation

subroutine clapll (integerN, complex, dimension( * )X, integerINCX, complex, dimension( * )Y, integerINCY, realSSMIN)

CLAPLL 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 COMPLEX 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 COMPLEX 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 101 of file clapll.f.

Author

Generated automatically by Doxygen for LAPACK from the source code.