_CORTH(3F)							    _CORTH(3F)

NAME    [Toc]    [Back]

     CORTH, SCORTH   -	EISPACK	routine.  Given	a COMPLEX GENERAL matrix, this
     subroutine	reduces	a submatrix situated in	rows and columns LOW through
     IGH to upper Hessenberg form by unitary similarity	transformations.

SYNOPSYS    [Toc]    [Back]

	  subroutine  corth(nm,	n, low,	igh, ar, ai, ortr, orti)
	  integer	   nm, n, low, igh
	  double precision ar(nm,n), ai(nm,n), ortr(igh), orti(igh)

	  subroutine scorth(nm,	n, low,	igh, ar, ai, ortr, orti)
	  integer	   nm, n, low, igh
	  real		   ar(nm,n), ai(nm,n), ortr(igh), orti(igh)

DESCRIPTION    [Toc]    [Back]

     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  CBAL.
     If	 CBAL  has not been used, set LOW=1, IGH=N.

     AR	and AI contain the real	and imaginary parts, respectively, of the
     complex input matrix.  On OUTPUT

     AR	and AI contain the real	and imaginary parts, respectively, of the
     Hessenberg	matrix.	 Information about the unitary transformations used in
     the reduction is stored in	the remaining triangles	under the Hessenberg
     matrix.

     ORTR and ORTI contain further information about the transformations.
     Only elements LOW through IGH are used.  Calls PYTHAG(A,B)	for sqrt(A**2
     + B**2).  Questions and comments should be	directed to B. S. Garbow,
     APPLIED MATHEMATICS DIVISION, ARGONNE NATIONAL LABORATORY


									PPPPaaaaggggeeee 1111