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NAME
     dlasq2 - DLASQ2 computes the singular values of  a  real  N-
     by-N unreduced  bidiagonal matrix with squared diagonal ele-
     ments in Q and  squared off-diagonal elements in E

SYNOPSIS
     SUBROUTINE DLASQ2( M, Q, E, QQ, EE, EPS, TOL2, SMALL2,  SUP,
               KEND, INFO )

     INTEGER INFO, KEND, M

     DOUBLE PRECISION EPS, SMALL2, SUP, TOL2

     DOUBLE PRECISION E( * ), EE( * ), Q( * ), QQ( * )



     #include <sunperf.h>

     void dlasq2(int m, double *q, double *e, double *qq,  double
               *ee,  double eps, double tol2, double small2, dou-
               ble *sup, int *kend, int *info) ;

PURPOSE
        DLASQ2 computes the singular  values  of  a  real  N-by-N
     unreduced
        bidiagonal matrix with squared diagonal elements in Q and
        squared off-diagonal elements in E. The  singular  values
     are
        computed to relative accuracy TOL, barring over/underflow
     or
        denormalization.


ARGUMENTS
     M         (input) INTEGER
               The number of rows and columns in the matrix. M >=
               0.

     Q         (output) DOUBLE PRECISION array, dimension (M)
               On normal  exit,  contains  the  squared  singular
               values.

     E         (workspace) DOUBLE PRECISION array, dimension (M)

     QQ        (input/output) DOUBLE PRECISION  array,  dimension
               (M)
               On entry, QQ contains the  squared  diagonal  ele-
               ments  of  the  bidiagonal  matrix  whose  SVD  is
               desired.  On exit, QQ is overwritten.

     EE        (input/output) DOUBLE PRECISION  array,  dimension
               (M)
               On entry,  EE(1:N-1)  contains  the  squared  off-
               diagonal  elements  of the bidiagonal matrix whose
               SVD is desired.  On exit, EE is overwritten.

     EPS       (input) DOUBLE PRECISION
               Machine epsilon.

     TOL2      (input) DOUBLE PRECISION
               Desired relative accuracy of computed  eigenvalues
               as defined in DLASQ1.

     SMALL2    (input) DOUBLE PRECISION
               A threshold value as defined in DLASQ1.

     SUP       (input/output) DOUBLE PRECISION
               Upper bound for the smallest eigenvalue.

     KEND      (input/output) INTEGER
               Index where minimum d occurs.

     INFO      (output) INTEGER
               = 0:  successful exit
               < 0:  if INFO = -i, the i-th argument had an ille-
               gal value
               > 0:  if INFO = i, the algorithm did not converge;
               i  specifies  how many superdiagonals did not con-
               verge.

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