_ORTHES(3F)_ORTHES(3F)NAME
ORTHES, SORTHES - EISPACK routine. Given a REAL GENERAL matrix, this
subroutine reduces a submatrix situated in rows and columns LOW through
IGH to upper Hessenberg form by orthogonal similarity transformations.
SYNOPSYS
subroutine orthes(nm, n, low, igh, a, ort)
integer nm, n, low, igh
double precision a(nm,n), ort(igh)
subroutine sorthes(nm, n, low, igh, a, ort)
integer nm, n, low, igh
real a(nm,n), ort(igh)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.
LOW and IGH are integers determined by the balancing subroutine BALANC.
If BALANC has not been used, set LOW=1, IGH=N.
A contains the input matrix. On OUTPUT
A contains the Hessenberg matrix. Information about the orthogonal
transformations used in the reduction is stored in the remaining triangle
under the Hessenberg matrix.
ORT contains further information about the transformations. only elements
LOW through IGH are used. Questions and comments should be directed to
B. S. Garbow, APPLIED MATHEMATICS DIVISION, ARGONNE NATIONAL LABORATORY
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