org.netlib.lapack
Class Slasq1
java.lang.Object
org.netlib.lapack.Slasq1
public class Slasq1
- extends java.lang.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
* =======
*
* SLASQ1 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, in the absence of
* denormalization, underflow and overflow. The algorithm was first
* presented 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,
*
* and the present implementation is described in "An implementation of
* the dqds Algorithm (Positive Case)", LAPACK Working Note.
*
* 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 (4*N)
*
* INFO (output) INTEGER
* = 0: successful exit
* < 0: if INFO = -i, the i-th argument had an illegal value
* > 0: the algorithm failed
* = 1, a split was marked by a positive value in E
* = 2, current block of Z not diagonalized after 30*N
* iterations (in inner while loop)
* = 3, termination criterion of outer while loop not met
* (program created more than N unreduced blocks)
*
* =====================================================================
*
* .. Parameters ..
|
Method Summary |
static void |
slasq1(int n,
float[] d,
int _d_offset,
float[] e,
int _e_offset,
float[] work,
int _work_offset,
intW info)
|
| Methods inherited from class java.lang.Object |
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait |
Slasq1
public Slasq1()
slasq1
public static void slasq1(int n,
float[] d,
int _d_offset,
float[] e,
int _e_offset,
float[] work,
int _work_offset,
intW info)