centos man page for dlarfg

dlarfg.f(3)							      LAPACK							       dlarfg.f(3)

NAME
       dlarfg.f -

SYNOPSIS
   Functions/Subroutines
       subroutine dlarfg (N, ALPHA, X, INCX, TAU)
	   DLARFG generates an elementary reflector (Householder matrix).

Function/Subroutine Documentation
   subroutine dlarfg (integerN, double precisionALPHA, double precision, dimension( * )X, integerINCX, double precisionTAU)
       DLARFG generates an elementary reflector (Householder matrix).

       Purpose:

	    DLARFG generates a real elementary reflector H of order n, such
	    that

		  H * ( alpha ) = ( beta ),   H**T * H = I.
		      (   x   )   (   0  )

	    where alpha and beta are scalars, and x is an (n-1)-element real
	    vector. H is represented in the form

		  H = I - tau * ( 1 ) * ( 1 v**T ) ,
				( v )

	    where tau is a real scalar and v is a real (n-1)-element
	    vector.

	    If the elements of x are all zero, then tau = 0 and H is taken to be
	    the unit matrix.

	    Otherwise  1 <= tau <= 2.

       Parameters:
	   N

		     N is INTEGER
		     The order of the elementary reflector.

	   ALPHA

		     ALPHA is DOUBLE PRECISION
		     On entry, the value alpha.
		     On exit, it is overwritten with the value beta.

	   X

		     X is DOUBLE PRECISION array, dimension
				    (1+(N-2)*abs(INCX))
		     On entry, the vector x.
		     On exit, it is overwritten with the vector v.

	   INCX

		     INCX is INTEGER
		     The increment between elements of X. INCX > 0.

	   TAU

		     TAU is DOUBLE PRECISION
		     The value tau.

       Author:
	   Univ. of Tennessee

	   Univ. of California Berkeley

	   Univ. of Colorado Denver

	   NAG Ltd.

       Date:
	   September 2012

       Definition at line 107 of file dlarfg.f.

Author
       Generated automatically by Doxygen for LAPACK from the source code.

Version 3.4.2							  Tue Sep 25 2012						       dlarfg.f(3)