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NAME
     slasq1 - SLASQ1 computes the singular values of  a  real  N-
     by-N bidiagonal  matrix with diagonal D and off-diagonal E

SYNOPSIS
     SUBROUTINE SLASQ1( N, D, E, WORK, INFO )

     INTEGER INFO, N

     REAL D( * ), E( * ), WORK( * )



     #include <sunperf.h>

     void slasq1(int n, float *d, float *e, int *info) ;

PURPOSE
     SLASQ1 computes the singular values of a real N-by-N bidiag-
     onal matrix with diagonal D and off-diagonal E. The singular
     values are  computed  to  high  relative  accuracy,  barring
     over/underflow   or   denormalization.   The   algorithm  is
     described in

     "Accurate singular values and differential  qd  algorithms,"
     by K. V. Fernando and B. N. Parlett,
     Numer. Math., Vol-67, No. 2, pp. 191-230,1994.

     See also
     "Implementation of differential qd algorithms," by
     K. V. Fernando and B. N. Parlett, Technical Report,
     Department  of  Mathematics,  University  of  California  at
     Berkeley, 1994 (Under preparation).


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

     D         (input/output) REAL array, dimension (N)
               On entry, D contains the diagonal elements of  the
               bidiagonal  matrix whose SVD is desired. On normal
               exit, D contains the singular values in decreasing
               order.

     E         (input/output) REAL array, dimension (N)
               On  entry,  elements  E(1:N-1)  contain  the  off-
               diagonal  elements  of the bidiagonal matrix whose
               SVD is desired.  On exit, E is overwritten.

     WORK      (workspace) REAL array, dimension (2*N)
     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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