ORTHES(3F)
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.
As shipped in IRIX 6.5. First release of IRIX 6.5.
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