_HTRIB3(3F)_HTRIB3(3F)NAME
HTRIB3, SHTRIB3 - EISPACK routine. This subroutine forms the
eigenvectors of a COMPLEX HERMITIAN matrix by back transforming those of
the corresponding real symmetric tridiagonal matrix determined by
HTRID3.
SYNOPSYS
subroutine htrib3(nm, n, a, tau, m, zr, zi)
integer nm, n, m
double precision a(nm,n), tau(2,n), zr(nm,m), zi(nm,m)
subroutine shtrib3(nm, n, a, tau, m, zr, zi)
integer nm, n, m
real a(nm,n), tau(2,n), zr(nm,m), zi(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.
A contains information about the unitary transformations used in the
reduction by HTRID3.
TAU contains further information about the transformations.
M IS the number of eigenvectors to be back transformed.
ZR contains the eigenvectors to be back transformed in its first M
columns. On OUTPUT
ZR and ZI contain the real and imaginary parts, respectively, of the
transformed eigenvectors in their first M columns. NOTE that the last
component of each returned vector is real and that vector Euclidean norms
are preserved. Questions and comments should be directed to B. S.
Garbow, APPLIED MATHEMATICS DIVISION, ARGONNE NATIONAL LABORATORY
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