All Packages  Class Hierarchy  This Package  Previous  Next  Index

Class org.netlib.lapack.Dlasq2

java.lang.Object
   |
   +----org.netlib.lapack.Dlasq2

public class Dlasq2

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
 *     =======
 *
 *     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 elements 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 illegal value
 *          > 0:  if INFO = i, the algorithm did not converge;  i
 *                specifies how many superdiagonals did not converge.
 *
 *  =====================================================================
 *
 *     .. Parameters ..

Dlasq2()

dlasq2(int, double[], int, double[], int, double[], int, double[], int, double, double, double, doubleW, intW, intW)

 public Dlasq2()

 public static void dlasq2(int m,
                           double q[],
                           int _q_offset,
                           double e[],
                           int _e_offset,
                           double qq[],
                           int _qq_offset,
                           double ee[],
                           int _ee_offset,
                           double eps,
                           double tol2,
                           double small2,
                           doubleW sup,
                           intW kend,
                           intW info)

All Packages  Class Hierarchy  This Package  Previous  Next  Index