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slarfgp.f(3)                        LAPACK                        slarfgp.f(3)

NAME
       slarfgp.f -

SYNOPSIS
   Functions/Subroutines
       subroutine slarfgp (N, ALPHA, X, INCX, TAU)
           SLARFGP generates an elementary reflector (Householder matrix) with
           non-negatibe beta.

Function/Subroutine Documentation
   subroutine slarfgp (integerN, realALPHA, real, dimension( * )X,
       integerINCX, realTAU)
       SLARFGP generates an elementary reflector (Householder matrix) with
       non-negatibe beta.

       Purpose:

            SLARFGP 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, beta is non-negative, 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.

       Parameters:
           N

                     N is INTEGER
                     The order of the elementary reflector.

           ALPHA

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

           X

                     X is REAL 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 REAL
                     The value tau.

       Author:
           Univ. of Tennessee

           Univ. of California Berkeley

           Univ. of Colorado Denver

           NAG Ltd.

       Date:
           September 2012

       Definition at line 105 of file slarfgp.f.

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

Version 3.4.2                   Sat Nov 16 2013                   slarfgp.f(3)