REBAK(3F)

REBAK, SREBAK - EISPACK routine. This subroutine forms the eigenvectors of a generalized SYMMETRIC eigensystem by back transforming those of the derived symmetric matrix determined by REDUC.

As shipped in IRIX 6.5.30. Unchanged since IRIX 6.5.

NAME
     REBAK, SREBAK   -  EISPACK routine.  This subroutine forms the
     eigenvectors of a generalized SYMMETRIC eigensystem by back transforming
     those of the derived symmetric matrix determined by  REDUC.


SYNOPSYS
          subroutine  rebak(nm, n, b, dl, m, z)
          integer          nm, n, m
          double precision b(nm,n), dl(n), z(nm,m)

          subroutine srebak(nm, n, b, dl, m, z)
          integer          nm, n, m
          real             b(nm,n), dl(n), z(nm,m)



DESCRIPTION
     On Input

     NM must be set to the row dimension of two-dimensional array parameters
     as declared in the calling program dimension statement.

     N is the order of the matrix system.

     B contains information about the similarity transformation (Cholesky
     decomposition) used in the reduction by  REDUC in its strict lower
     triangle.

     DL contains further information about the transformation.

     M is the number of eigenvectors to be back transformed.

     Z contains the eigenvectors to be back transformed in its first M
     columns.  On Output

     Z contains the transformed eigenvectors in its first M columns.
     Questions and comments should be directed to B. S. Garbow, APPLIED
     MATHEMATICS DIVISION, ARGONNE NATIONAL LABORATORY