1DLAPLL(1)           LAPACK auxiliary routine (version 3.2)           DLAPLL(1)
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NAME

6       DLAPLL - two column vectors X and Y, let   A = ( X Y )
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SYNOPSIS

9       SUBROUTINE DLAPLL( N, X, INCX, Y, INCY, SSMIN )
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11           INTEGER        INCX, INCY, N
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13           DOUBLE         PRECISION SSMIN
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15           DOUBLE         PRECISION X( * ), Y( * )
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PURPOSE

18       Given two column vectors X and Y, let The subroutine first computes the
19       QR factorization of A = Q*R, and then computes the SVD  of  the  2-by-2
20       upper triangular matrix R.  The smaller singular value of R is returned
21       in SSMIN, which is used as the measurement of the linear dependency  of
22       the vectors X and Y.
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ARGUMENTS

25       N       (input) INTEGER
26               The length of the vectors X and Y.
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28       X       (input/output) DOUBLE PRECISION array,
29               dimension  (1+(N-1)*INCX)  On entry, X contains the N-vector X.
30               On exit, X is overwritten.
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32       INCX    (input) INTEGER
33               The increment between successive elements of X. INCX > 0.
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35       Y       (input/output) DOUBLE PRECISION array,
36               dimension (1+(N-1)*INCY) On entry, Y contains the  N-vector  Y.
37               On exit, Y is overwritten.
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39       INCY    (input) INTEGER
40               The increment between successive elements of Y. INCY > 0.
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42       SSMIN   (output) DOUBLE PRECISION
43               The smallest singular value of the N-by-2 matrix A = ( X Y ).
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47 LAPACK auxiliary routine (versionNo3v.e2m)ber 2008                       DLAPLL(1)