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Class org.netlib.lapack.Dlasq1

java.lang.Object
   |
   +----org.netlib.lapack.Dlasq1

public class Dlasq1

extends Object

Following is the description from the original
Fortran source.  For each array argument, the Java
version will include an integer offset parameter, so
the arguments may not match the description exactly.
Contact seymour@cs.utk.edu with any questions.

 *     ..
 *
 *     Purpose
 *     =======
 *
 *     DLASQ1 computes the singular values of a real N-by-N bidiagonal
 *     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) DOUBLE PRECISION 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) DOUBLE PRECISION 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) DOUBLE PRECISION array, dimension (2*N)
 *
 *  INFO    (output) INTEGER
 *          = 0:  successful exit
 *          < 0:  if INFO = -i, the i-th argument had an illegal value
 *          > 0:  if INFO = i, the algorithm did not converge;  i
 *                specifies how many superdiagonals did not converge.
 *
 *  =====================================================================
 *
 *     .. Parameters ..

Dlasq1()

dlasq1(int, double[], int, double[], int, double[], int, intW)

 public Dlasq1()

 public static void dlasq1(int n,
                           double d[],
                           int _d_offset,
                           double e[],
                           int _e_offset,
                           double work[],
                           int _work_offset,
                           intW info)

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