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Class org.netlib.lapack.Dggbak

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

public class Dggbak
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 * ======= * * DGGBAK forms the right or left eigenvectors of a real generalized * eigenvalue problem A*x = lambda*B*x, by backward transformation on * the computed eigenvectors of the balanced pair of matrices output by * DGGBAL. * * Arguments * ========= * * JOB (input) CHARACTER*1 * Specifies the type of backward transformation required: * = 'N': do nothing, return immediately; * = 'P': do backward transformation for permutation only; * = 'S': do backward transformation for scaling only; * = 'B': do backward transformations for both permutation and * scaling. * JOB must be the same as the argument JOB supplied to DGGBAL. * * SIDE (input) CHARACTER*1 * = 'R': V contains right eigenvectors; * = 'L': V contains left eigenvectors. * * N (input) INTEGER * The number of rows of the matrix V. N >= 0. * * ILO (input) INTEGER * IHI (input) INTEGER * The integers ILO and IHI determined by DGGBAL. * 1 <= ILO <= IHI <= N, if N > 0; ILO=1 and IHI=0, if N=0. * * LSCALE (input) DOUBLE PRECISION array, dimension (N) * Details of the permutations and/or scaling factors applied * to the left side of A and B, as returned by DGGBAL. * * RSCALE (input) DOUBLE PRECISION array, dimension (N) * Details of the permutations and/or scaling factors applied * to the right side of A and B, as returned by DGGBAL. * * M (input) INTEGER * The number of columns of the matrix V. M >= 0. * * V (input/output) DOUBLE PRECISION array, dimension (LDV,M) * On entry, the matrix of right or left eigenvectors to be * transformed, as returned by DTGEVC. * On exit, V is overwritten by the transformed eigenvectors. * * LDV (input) INTEGER * The leading dimension of the matrix V. LDV >= max(1,N). * * INFO (output) INTEGER * = 0: successful exit. * < 0: if INFO = -i, the i-th argument had an illegal value. * * Further Details * =============== * * See R.C. Ward, Balancing the generalized eigenvalue problem, * SIAM J. Sci. Stat. Comp. 2 (1981), 141-152. * * ===================================================================== * * .. Local Scalars ..


Constructor Index

 o Dggbak()

Method Index

 o dggbak(String, String, int, int, int, double[], int, double[], int, int, double[], int, int, intW)

Constructors

 o Dggbak
 public Dggbak()

Methods

 o dggbak
 public static void dggbak(String job,
                           String side,
                           int n,
                           int ilo,
                           int ihi,
                           double lscale[],
                           int _lscale_offset,
                           double rscale[],
                           int _rscale_offset,
                           int m,
                           double v[],
                           int _v_offset,
                           int ldv,
                           intW info)

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